diff --git a/mlir/include/mlir-c/Dialect/Quant.h b/mlir/include/mlir-c/Dialect/Quant.h
new file mode 100644
--- /dev/null
+++ b/mlir/include/mlir-c/Dialect/Quant.h
@@ -0,0 +1,199 @@
+//===-- mlir-c/Dialect/LLVM.h - C API for LLVM --------------------*- C -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM
+// Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef MLIR_C_DIALECT_QUANT_H
+#define MLIR_C_DIALECT_QUANT_H
+
+#include "mlir-c/IR.h"
+#include "mlir-c/Registration.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+MLIR_DECLARE_CAPI_DIALECT_REGISTRATION(quant, quant);
+
+//===---------------------------------------------------------------------===//
+// QuantizedType
+//===---------------------------------------------------------------------===//
+
+/// Returns `true` if the given type is a quantization dialect type.
+MLIR_CAPI_EXPORTED bool mlirTypeIsAQuantizedType(MlirType type);
+
+/// Returns the bit flag used to indicate signedness of a quantized type.
+MLIR_CAPI_EXPORTED unsigned mlirQuantizedTypeGetSignedFlag();
+
+/// Returns the minimum possible value stored by a quantized type.
+MLIR_CAPI_EXPORTED int64_t mlirQuantizedTypeGetDefaultMinimumForInteger(
+    bool isSigned, unsigned integralWidth);
+
+/// Returns the maximum possible value stored by a quantized type.
+MLIR_CAPI_EXPORTED int64_t mlirQuantizedTypeGetDefaultMaximumForInteger(
+    bool isSigned, unsigned integralWidth);
+
+/// Gets the original type approximated by the given quantized type.
+MLIR_CAPI_EXPORTED MlirType mlirQuantizedTypeGetExpressedType(MlirType type);
+
+/// Gets the flags associated with the given quantized type.
+MLIR_CAPI_EXPORTED unsigned mlirQuantizedTypeGetFlags(MlirType type);
+
+/// Returns `true` if the given type is signed, `false` otherwise.
+MLIR_CAPI_EXPORTED bool mlirQuantizedTypeIsSigned(MlirType type);
+
+/// Returns the underlying type used to store the values.
+MLIR_CAPI_EXPORTED MlirType mlirQuantizedTypeGetStorageType(MlirType type);
+
+/// Returns the minimum value that the storage type of the given quantized type
+/// can take.
+MLIR_CAPI_EXPORTED int64_t mlirQuantizedTypeGetStorageTypeMin(MlirType type);
+
+/// Returns the maximum value that the storage type of the given quantized type
+/// can take.
+MLIR_CAPI_EXPORTED int64_t mlirQuantizedTypeGetStorageTypeMax(MlirType type);
+
+/// Returns the integral bitwidth that the storage type of the given quantized
+/// type can represent exactly.
+MLIR_CAPI_EXPORTED unsigned
+mlirQuantizedTypeGetStorageTypeIntegralWidth(MlirType type);
+
+/// Returns `true` if the `candidate` type is compatible with the given
+/// quantized `type`.
+MLIR_CAPI_EXPORTED bool
+mlirQuantizedTypeIsCompatibleExpressedType(MlirType type, MlirType candidate);
+
+/// Returns the element type of the given quantized type as another quantized
+/// type.
+MLIR_CAPI_EXPORTED MlirType
+mlirQuantizedTypeGetQuantizedElementType(MlirType type);
+
+/// Casts from a type based on the storage type of the given type to a
+/// corresponding type based on the given type. Returns a null type if the cast
+/// is not valid.
+MLIR_CAPI_EXPORTED MlirType
+mlirQuantizedTypeCastFromStorageType(MlirType type, MlirType candidate);
+
+/// Casts from a type based on a quantized type to a corresponding typed based
+/// on the storage type. Returns a null type if the cast is not valid.
+MLIR_CAPI_EXPORTED MlirType mlirQuantizedTypeCastToStorageType(MlirType type);
+
+/// Casts from a type based on the expressed type of the given type to a
+/// corresponding type based on the given type. Returns a null type if the cast
+/// is not valid.
+MLIR_CAPI_EXPORTED MlirType
+mlirQuantizedTypeCastFromExpressedType(MlirType type, MlirType candidate);
+
+/// Casts from a type based on a quantized type to a corresponding typed based
+/// on the expressed type. Returns a null type if the cast is not valid.
+MLIR_CAPI_EXPORTED MlirType mlirQuantizedTypeCastToExpressedType(MlirType type);
+
+/// Casts from a type based on the expressed type of the given quantized type to
+/// equivalent type based on storage type of the same quantized type.
+MLIR_CAPI_EXPORTED MlirType
+mlirQuantizedTypeCastExpressedToStorageType(MlirType type, MlirType candidate);
+
+//===---------------------------------------------------------------------===//
+// AnyQuantizedType
+//===---------------------------------------------------------------------===//
+
+/// Returns `true` if the given type is an AnyQuantizedType.
+MLIR_CAPI_EXPORTED bool mlirTypeIsAAnyQuantizedType(MlirType type);
+
+/// Creates an instance of AnyQuantizedType with the given parameters in the
+/// same context as `storageType` and returns it. The instance is owned by the
+/// context.
+MLIR_CAPI_EXPORTED MlirType mlirAnyQuantizedTypeGet(unsigned flags,
+                                                    MlirType storageType,
+                                                    MlirType expressedType,
+                                                    int64_t storageTypeMin,
+                                                    int64_t storageTypeMax);
+
+//===---------------------------------------------------------------------===//
+// UniformQuantizedType
+//===---------------------------------------------------------------------===//
+
+/// Returns `true` if the given type is a UniformQuantizedType.
+MLIR_CAPI_EXPORTED bool mlirTypeIsAUniformQuantizedType(MlirType type);
+
+/// Creates an instance of UniformQuantizedType with the given parameters in the
+/// same context as `storageType` and returns it. The instance is owned by the
+/// context.
+MLIR_CAPI_EXPORTED MlirType mlirUniformQuantizedTypeGet(
+    unsigned flags, MlirType storageType, MlirType expressedType, double scale,
+    int64_t zeroPoint, int64_t storageTypeMin, int64_t storageTypeMax);
+
+/// Returns the scale of the given uniform quantized type.
+MLIR_CAPI_EXPORTED double mlirUniformQuantizedTypeGetScale(MlirType type);
+
+/// Returns the zero point of the given uniform quantized type.
+MLIR_CAPI_EXPORTED int64_t mlirUniformQuantizedTypeGetZeroPoint(MlirType type);
+
+/// Returns `true` if the given uniform quantized type is fixed-point.
+MLIR_CAPI_EXPORTED bool mlirUniformQuantizedTypeIsFixedPoint(MlirType type);
+
+//===---------------------------------------------------------------------===//
+// UniformQuantizedPerAxisType
+//===---------------------------------------------------------------------===//
+
+/// Returns `true` if the given type is a UniformQuantizedPerAxisType.
+MLIR_CAPI_EXPORTED bool mlirTypeIsAUniformQuantizedPerAxisType(MlirType type);
+
+/// Creates an instance of UniformQuantizedPerAxisType with the given parameters
+/// in the same context as `storageType` and returns it. `scales` and
+/// `zeroPoints` point to `nDims` number of elements. The instance is owned
+/// by the context.
+MLIR_CAPI_EXPORTED MlirType mlirUniformQuantizedPerAxisTypeGet(
+    unsigned flags, MlirType storageType, MlirType expressedType,
+    intptr_t nDims, double *scales, int64_t *zeroPoints,
+    int32_t quantizedDimension, int64_t storageTypeMin, int64_t storageTypeMax);
+
+/// Returns the number of axes in the given quantized per-axis type.
+MLIR_CAPI_EXPORTED intptr_t
+mlirUniformQuantizedPerAxisTypeGetNumDims(MlirType type);
+
+/// Returns `pos`-th scale of the given quantized per-axis type.
+MLIR_CAPI_EXPORTED double mlirUniformQuantizedPerAxisTypeGetScale(MlirType type,
+                                                                  intptr_t pos);
+
+/// Returns `pos`-th zero point of the given quantized per-axis type.
+MLIR_CAPI_EXPORTED int64_t
+mlirUniformQuantizedPerAxisTypeGetZeroPoint(MlirType type, intptr_t pos);
+
+/// Returns the index of the quantized dimension in the given quantized per-axis
+/// type.
+MLIR_CAPI_EXPORTED int32_t
+mlirUniformQuantizedPerAxisTypeGetQuantizedDimension(MlirType type);
+
+/// Returns `true` if the given uniform quantized per-axis type is fixed-point.
+MLIR_CAPI_EXPORTED bool
+mlirUniformQuantizedPerAxisTypeIsFixedPoint(MlirType type);
+
+//===---------------------------------------------------------------------===//
+// CalibratedQuantizedType
+//===---------------------------------------------------------------------===//
+
+/// Returns `true` if the given type is a CalibratedQuantizedType.
+MLIR_CAPI_EXPORTED bool mlirTypeIsACalibratedQuantizedType(MlirType type);
+
+/// Creates an instance of CalibratedQuantizedType with the given parameters
+/// in the same context as `expressedType` and returns it. The instance is owned
+/// by the context.
+MLIR_CAPI_EXPORTED MlirType
+mlirCalibratedQuantizedTypeGet(MlirType expressedType, double min, double max);
+
+/// Returns the min value of the given calibrated quantized type.
+MLIR_CAPI_EXPORTED double mlirCalibratedQuantizedTypeGetMin(MlirType type);
+
+/// Returns the max value of the given calibrated quantized type.
+MLIR_CAPI_EXPORTED double mlirCalibratedQuantizedTypeGetMax(MlirType type);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // MLIR_C_DIALECT_QUANT_H
diff --git a/mlir/lib/CAPI/Dialect/CMakeLists.txt b/mlir/lib/CAPI/Dialect/CMakeLists.txt
--- a/mlir/lib/CAPI/Dialect/CMakeLists.txt
+++ b/mlir/lib/CAPI/Dialect/CMakeLists.txt
@@ -97,3 +97,12 @@
   MLIRCAPIIR
   MLIRTensor
 )
+
+add_mlir_upstream_c_api_library(MLIRCAPIQuant
+  Quant.cpp
+
+  PARTIAL_SOURCES_INTENDED
+  LINK_LIBS PUBLIC
+  MLIRCAPIIR
+  MLIRQuant
+)
diff --git a/mlir/lib/CAPI/Dialect/Quant.cpp b/mlir/lib/CAPI/Dialect/Quant.cpp
new file mode 100644
--- /dev/null
+++ b/mlir/lib/CAPI/Dialect/Quant.cpp
@@ -0,0 +1,224 @@
+//===- LLVM.cpp - C Interface for Quant dialect ---------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir-c/Dialect/Quant.h"
+#include "mlir/CAPI/Registration.h"
+#include "mlir/Dialect/Quant/QuantOps.h"
+#include "mlir/Dialect/Quant/QuantTypes.h"
+
+using namespace mlir;
+
+MLIR_DEFINE_CAPI_DIALECT_REGISTRATION(quant, quant, quant::QuantizationDialect)
+
+//===---------------------------------------------------------------------===//
+// QuantizedType
+//===---------------------------------------------------------------------===//
+
+bool mlirTypeIsAQuantizedType(MlirType type) {
+  return unwrap(type).isa<quant::QuantizedType>();
+}
+
+unsigned mlirQuantizedTypeGetSignedFlag() {
+  return quant::QuantizationFlags::Signed;
+}
+
+int64_t mlirQuantizedTypeGetDefaultMinimumForInteger(bool isSigned,
+                                                     unsigned integralWidth) {
+  return quant::QuantizedType::getDefaultMinimumForInteger(isSigned,
+                                                           integralWidth);
+}
+
+int64_t mlirQuantizedTypeGetDefaultMaximumForInteger(bool isSigned,
+                                                     unsigned integralWidth) {
+  return quant::QuantizedType::getDefaultMaximumForInteger(isSigned,
+                                                           integralWidth);
+}
+
+MlirType mlirQuantizedTypeGetExpressedType(MlirType type) {
+  return wrap(unwrap(type).cast<quant::QuantizedType>().getExpressedType());
+}
+
+unsigned mlirQuantizedTypeGetFlags(MlirType type) {
+  return unwrap(type).cast<quant::QuantizedType>().getFlags();
+}
+
+bool mlirQuantizedTypeIsSigned(MlirType type) {
+  return unwrap(type).cast<quant::QuantizedType>().isSigned();
+}
+
+MlirType mlirQuantizedTypeGetStorageType(MlirType type) {
+  return wrap(unwrap(type).cast<quant::QuantizedType>().getStorageType());
+}
+
+int64_t mlirQuantizedTypeGetStorageTypeMin(MlirType type) {
+  return unwrap(type).cast<quant::QuantizedType>().getStorageTypeMin();
+}
+
+int64_t mlirQuantizedTypeGetStorageTypeMax(MlirType type) {
+  return unwrap(type).cast<quant::QuantizedType>().getStorageTypeMax();
+}
+
+unsigned mlirQuantizedTypeGetStorageTypeIntegralWidth(MlirType type) {
+  return unwrap(type)
+      .cast<quant::QuantizedType>()
+      .getStorageTypeIntegralWidth();
+}
+
+bool mlirQuantizedTypeIsCompatibleExpressedType(MlirType type,
+                                                MlirType candidate) {
+  return unwrap(type).cast<quant::QuantizedType>().isCompatibleExpressedType(
+      unwrap(candidate));
+}
+
+MlirType mlirQuantizedTypeGetQuantizedElementType(MlirType type) {
+  return wrap(quant::QuantizedType::getQuantizedElementType(unwrap(type)));
+}
+
+MlirType mlirQuantizedTypeCastFromStorageType(MlirType type,
+                                              MlirType candidate) {
+  return wrap(unwrap(type).cast<quant::QuantizedType>().castFromStorageType(
+      unwrap(candidate)));
+}
+
+MlirType mlirQuantizedTypeCastToStorageType(MlirType type) {
+  return wrap(quant::QuantizedType::castToStorageType(
+      unwrap(type).cast<quant::QuantizedType>()));
+}
+
+MlirType mlirQuantizedTypeCastFromExpressedType(MlirType type,
+                                                MlirType candidate) {
+  return wrap(unwrap(type).cast<quant::QuantizedType>().castFromExpressedType(
+      unwrap(candidate)));
+}
+
+MlirType mlirQuantizedTypeCastToExpressedType(MlirType type) {
+  return wrap(quant::QuantizedType::castToExpressedType(unwrap(type)));
+}
+
+MlirType mlirQuantizedTypeCastExpressedToStorageType(MlirType type,
+                                                     MlirType candidate) {
+  return wrap(
+      unwrap(type).cast<quant::QuantizedType>().castExpressedToStorageType(
+          unwrap(candidate)));
+}
+
+//===---------------------------------------------------------------------===//
+// AnyQuantizedType
+//===---------------------------------------------------------------------===//
+
+bool mlirTypeIsAAnyQuantizedType(MlirType type) {
+  return unwrap(type).isa<quant::AnyQuantizedType>();
+}
+
+MlirType mlirAnyQuantizedTypeGet(unsigned flags, MlirType storageType,
+                                 MlirType expressedType, int64_t storageTypeMin,
+                                 int64_t storageTypeMax) {
+  return wrap(quant::AnyQuantizedType::get(flags, unwrap(storageType),
+                                           unwrap(expressedType),
+                                           storageTypeMin, storageTypeMax));
+}
+
+//===---------------------------------------------------------------------===//
+// UniformQuantizedType
+//===---------------------------------------------------------------------===//
+
+bool mlirTypeIsAUniformQuantizedType(MlirType type) {
+  return unwrap(type).isa<quant::UniformQuantizedType>();
+}
+
+MlirType mlirUniformQuantizedTypeGet(unsigned flags, MlirType storageType,
+                                     MlirType expressedType, double scale,
+                                     int64_t zeroPoint, int64_t storageTypeMin,
+                                     int64_t storageTypeMax) {
+  return wrap(quant::UniformQuantizedType::get(
+      flags, unwrap(storageType), unwrap(expressedType), scale, zeroPoint,
+      storageTypeMin, storageTypeMax));
+}
+
+double mlirUniformQuantizedTypeGetScale(MlirType type) {
+  return unwrap(type).cast<quant::UniformQuantizedType>().getScale();
+}
+
+int64_t mlirUniformQuantizedTypeGetZeroPoint(MlirType type) {
+  return unwrap(type).cast<quant::UniformQuantizedType>().getZeroPoint();
+}
+
+bool mlirUniformQuantizedTypeIsFixedPoint(MlirType type) {
+  return unwrap(type).cast<quant::UniformQuantizedType>().isFixedPoint();
+}
+
+//===---------------------------------------------------------------------===//
+// UniformQuantizedPerAxisType
+//===---------------------------------------------------------------------===//
+
+bool mlirTypeIsAUniformQuantizedPerAxisType(MlirType type) {
+  return unwrap(type).isa<quant::UniformQuantizedPerAxisType>();
+}
+
+MlirType mlirUniformQuantizedPerAxisTypeGet(
+    unsigned flags, MlirType storageType, MlirType expressedType,
+    intptr_t nDims, double *scales, int64_t *zeroPoints,
+    int32_t quantizedDimension, int64_t storageTypeMin,
+    int64_t storageTypeMax) {
+  return wrap(quant::UniformQuantizedPerAxisType::get(
+      flags, unwrap(storageType), unwrap(expressedType),
+      llvm::makeArrayRef(scales, nDims), llvm::makeArrayRef(zeroPoints, nDims),
+      quantizedDimension, storageTypeMin, storageTypeMax));
+}
+
+intptr_t mlirUniformQuantizedPerAxisTypeGetNumDims(MlirType type) {
+  return unwrap(type)
+      .cast<quant::UniformQuantizedPerAxisType>()
+      .getScales()
+      .size();
+}
+
+double mlirUniformQuantizedPerAxisTypeGetScale(MlirType type, intptr_t pos) {
+  return unwrap(type)
+      .cast<quant::UniformQuantizedPerAxisType>()
+      .getScales()[pos];
+}
+
+int64_t mlirUniformQuantizedPerAxisTypeGetZeroPoint(MlirType type,
+                                                    intptr_t pos) {
+  return unwrap(type)
+      .cast<quant::UniformQuantizedPerAxisType>()
+      .getZeroPoints()[pos];
+}
+
+int32_t mlirUniformQuantizedPerAxisTypeGetQuantizedDimension(MlirType type) {
+  return unwrap(type)
+      .cast<quant::UniformQuantizedPerAxisType>()
+      .getQuantizedDimension();
+}
+
+bool mlirUniformQuantizedPerAxisTypeIsFixedPoint(MlirType type) {
+  return unwrap(type).cast<quant::UniformQuantizedPerAxisType>().isFixedPoint();
+}
+
+//===---------------------------------------------------------------------===//
+// CalibratedQuantizedType
+//===---------------------------------------------------------------------===//
+
+bool mlirTypeIsACalibratedQuantizedType(MlirType type) {
+  return unwrap(type).isa<quant::CalibratedQuantizedType>();
+}
+
+MlirType mlirCalibratedQuantizedTypeGet(MlirType expressedType, double min,
+                                        double max) {
+  return wrap(
+      quant::CalibratedQuantizedType::get(unwrap(expressedType), min, max));
+}
+
+double mlirCalibratedQuantizedTypeGetMin(MlirType type) {
+  return unwrap(type).cast<quant::CalibratedQuantizedType>().getMin();
+}
+
+double mlirCalibratedQuantizedTypeGetMax(MlirType type) {
+  return unwrap(type).cast<quant::CalibratedQuantizedType>().getMax();
+}
diff --git a/mlir/test/CAPI/CMakeLists.txt b/mlir/test/CAPI/CMakeLists.txt
--- a/mlir/test/CAPI/CMakeLists.txt
+++ b/mlir/test/CAPI/CMakeLists.txt
@@ -58,3 +58,11 @@
     MLIRCAPIRegistration
     MLIRCAPISparseTensor
 )
+
+_add_capi_test_executable(mlir-capi-quant-test
+  quant.c
+  LINK_LIBS PRIVATE
+    MLIRCAPIIR
+    MLIRCAPIRegistration
+    MLIRCAPIQuant
+)
diff --git a/mlir/test/CAPI/quant.c b/mlir/test/CAPI/quant.c
new file mode 100644
--- /dev/null
+++ b/mlir/test/CAPI/quant.c
@@ -0,0 +1,239 @@
+//===- quant.c - Test of Quant dialect C API ------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM
+// Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// RUN: mlir-capi-quant-test 2>&1 | FileCheck %s
+
+#include "mlir-c/Dialect/Quant.h"
+#include "mlir-c/BuiltinTypes.h"
+#include "mlir-c/IR.h"
+
+#include <assert.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+// CHECK-LABEL: testTypeHierarchy
+static void testTypeHierarchy(MlirContext ctx) {
+  fprintf(stderr, "testTypeHierarchy\n");
+
+  MlirType i8 = mlirIntegerTypeGet(ctx, 8);
+  MlirType any = mlirTypeParseGet(
+      ctx, mlirStringRefCreateFromCString("!quant.any<i8<-8:7>:f32>"));
+  MlirType uniform =
+      mlirTypeParseGet(ctx, mlirStringRefCreateFromCString(
+                                "!quant.uniform<i8<-8:7>:f32, 0.99872:127>"));
+  MlirType perAxis = mlirTypeParseGet(
+      ctx, mlirStringRefCreateFromCString(
+               "!quant.uniform<i8:f32:1, {2.0e+2,0.99872:120}>"));
+  MlirType calibrated = mlirTypeParseGet(
+      ctx,
+      mlirStringRefCreateFromCString("!quant.calibrated<f32<-0.998:1.2321>>"));
+
+  // The parser itself is checked in C++ dialect tests.
+  assert(!mlirTypeIsNull(any) && "couldn't parse AnyQuantizedType");
+  assert(!mlirTypeIsNull(uniform) && "couldn't parse UniformQuantizedType");
+  assert(!mlirTypeIsNull(perAxis) &&
+         "couldn't parse UniformQuantizedPerAxisType");
+  assert(!mlirTypeIsNull(calibrated) &&
+         "couldn't parse CalibratedQuantizedType");
+
+  // CHECK: i8 isa QuantizedType: 0
+  fprintf(stderr, "i8 isa QuantizedType: %d\n", mlirTypeIsAQuantizedType(i8));
+  // CHECK: any isa QuantizedType: 1
+  fprintf(stderr, "any isa QuantizedType: %d\n", mlirTypeIsAQuantizedType(any));
+  // CHECK: uniform isa QuantizedType: 1
+  fprintf(stderr, "uniform isa QuantizedType: %d\n",
+          mlirTypeIsAQuantizedType(uniform));
+  // CHECK: perAxis isa QuantizedType: 1
+  fprintf(stderr, "perAxis isa QuantizedType: %d\n",
+          mlirTypeIsAQuantizedType(perAxis));
+  // CHECK: calibrated isa QuantizedType: 1
+  fprintf(stderr, "calibrated isa QuantizedType: %d\n",
+          mlirTypeIsAQuantizedType(calibrated));
+
+  // CHECK: any isa AnyQuantizedType: 1
+  fprintf(stderr, "any isa AnyQuantizedType: %d\n",
+          mlirTypeIsAAnyQuantizedType(any));
+  // CHECK: uniform isa UniformQuantizedType: 1
+  fprintf(stderr, "uniform isa UniformQuantizedType: %d\n",
+          mlirTypeIsAUniformQuantizedType(uniform));
+  // CHECK: perAxis isa UniformQuantizedPerAxisType: 1
+  fprintf(stderr, "perAxis isa UniformQuantizedPerAxisType: %d\n",
+          mlirTypeIsAUniformQuantizedPerAxisType(perAxis));
+  // CHECK: calibrated isa CalibratedQuantizedType: 1
+  fprintf(stderr, "calibrated isa CalibratedQuantizedType: %d\n",
+          mlirTypeIsACalibratedQuantizedType(calibrated));
+
+  // CHECK: perAxis isa UniformQuantizedType: 0
+  fprintf(stderr, "perAxis isa UniformQuantizedType: %d\n",
+          mlirTypeIsAUniformQuantizedType(perAxis));
+  // CHECK: uniform isa CalibratedQuantizedType: 0
+  fprintf(stderr, "uniform isa CalibratedQuantizedType: %d\n",
+          mlirTypeIsACalibratedQuantizedType(uniform));
+  fprintf(stderr, "\n");
+}
+
+// CHECK-LABEL: testAnyQuantizedType
+void testAnyQuantizedType(MlirContext ctx) {
+  fprintf(stderr, "testAnyQuantizedType\n");
+
+  MlirType anyParsed = mlirTypeParseGet(
+      ctx, mlirStringRefCreateFromCString("!quant.any<i8<-8:7>:f32>"));
+
+  MlirType i8 = mlirIntegerTypeGet(ctx, 8);
+  MlirType f32 = mlirF32TypeGet(ctx);
+  MlirType any =
+      mlirAnyQuantizedTypeGet(mlirQuantizedTypeGetSignedFlag(), i8, f32, -8, 7);
+
+  // CHECK: flags: 1
+  fprintf(stderr, "flags: %u\n", mlirQuantizedTypeGetFlags(any));
+  // CHECK: signed: 1
+  fprintf(stderr, "signed: %u\n", mlirQuantizedTypeIsSigned(any));
+  // CHECK: storage type: i8
+  fprintf(stderr, "storage type: ");
+  mlirTypeDump(mlirQuantizedTypeGetStorageType(any));
+  fprintf(stderr, "\n");
+  // CHECK: expressed type: f32
+  fprintf(stderr, "expressed type: ");
+  mlirTypeDump(mlirQuantizedTypeGetExpressedType(any));
+  fprintf(stderr, "\n");
+  // CHECK: storage min: -8
+  fprintf(stderr, "storage min: %" PRId64 "\n",
+          mlirQuantizedTypeGetStorageTypeMin(any));
+  // CHECK: storage max: 7
+  fprintf(stderr, "storage max: %" PRId64 "\n",
+          mlirQuantizedTypeGetStorageTypeMax(any));
+  // CHECK: storage width: 8
+  fprintf(stderr, "storage width: %u\n",
+          mlirQuantizedTypeGetStorageTypeIntegralWidth(any));
+  // CHECK: quantized element type: !quant.any<i8<-8:7>:f32>
+  fprintf(stderr, "quantized element type: ");
+  mlirTypeDump(mlirQuantizedTypeGetQuantizedElementType(any));
+  fprintf(stderr, "\n");
+
+  // CHECK: equal: 1
+  fprintf(stderr, "equal: %d\n", mlirTypeEqual(anyParsed, any));
+  // CHECK: !quant.any<i8<-8:7>:f32>
+  mlirTypeDump(any);
+  fprintf(stderr, "\n\n");
+}
+
+// CHECK-LABEL: testUniformType
+void testUniformType(MlirContext ctx) {
+  fprintf(stderr, "testUniformType\n");
+
+  MlirType uniformParsed =
+      mlirTypeParseGet(ctx, mlirStringRefCreateFromCString(
+                                "!quant.uniform<i8<-8:7>:f32, 0.99872:127>"));
+
+  MlirType i8 = mlirIntegerTypeGet(ctx, 8);
+  MlirType f32 = mlirF32TypeGet(ctx);
+  MlirType uniform = mlirUniformQuantizedTypeGet(
+      mlirQuantizedTypeGetSignedFlag(), i8, f32, 0.99872, 127, -8, 7);
+
+  // CHECK: scale: 0.998720
+  fprintf(stderr, "scale: %lf\n", mlirUniformQuantizedTypeGetScale(uniform));
+  // CHECK: zero point: 127
+  fprintf(stderr, "zero point: %" PRId64 "\n",
+          mlirUniformQuantizedTypeGetZeroPoint(uniform));
+  // CHECK: fixed point: 0
+  fprintf(stderr, "fixed point: %d\n",
+          mlirUniformQuantizedTypeIsFixedPoint(uniform));
+
+  // CHECK: equal: 1
+  fprintf(stderr, "equal: %d\n", mlirTypeEqual(uniform, uniformParsed));
+  // CHECK: !quant.uniform<i8<-8:7>:f32, 9.987200e-01:127>
+  mlirTypeDump(uniform);
+  fprintf(stderr, "\n\n");
+}
+
+// CHECK-LABEL: testUniformPerAxisType
+void testUniformPerAxisType(MlirContext ctx) {
+  fprintf(stderr, "testUniformPerAxisType\n");
+
+  MlirType perAxisParsed = mlirTypeParseGet(
+      ctx, mlirStringRefCreateFromCString(
+               "!quant.uniform<i8:f32:1, {2.0e+2,0.99872:120}>"));
+
+  MlirType i8 = mlirIntegerTypeGet(ctx, 8);
+  MlirType f32 = mlirF32TypeGet(ctx);
+  double scales[] = {200.0, 0.99872};
+  int64_t zeroPoints[] = {0, 120};
+  MlirType perAxis = mlirUniformQuantizedPerAxisTypeGet(
+      mlirQuantizedTypeGetSignedFlag(), i8, f32,
+      /*nDims=*/2, scales, zeroPoints,
+      /*quantizedDimension=*/1,
+      mlirQuantizedTypeGetDefaultMinimumForInteger(/*isSigned=*/true,
+                                                   /*integralWidth=*/8),
+      mlirQuantizedTypeGetDefaultMaximumForInteger(/*isSigned=*/true,
+                                                   /*integralWidth=*/8));
+
+  // CHECK: num dims: 2
+  fprintf(stderr, "num dims: %" PRIdPTR "\n",
+          mlirUniformQuantizedPerAxisTypeGetNumDims(perAxis));
+  // CHECK: scale 0: 200.000000
+  fprintf(stderr, "scale 0: %lf\n",
+          mlirUniformQuantizedPerAxisTypeGetScale(perAxis, 0));
+  // CHECK: scale 1: 0.998720
+  fprintf(stderr, "scale 1: %lf\n",
+          mlirUniformQuantizedPerAxisTypeGetScale(perAxis, 1));
+  // CHECK: zero point 0: 0
+  fprintf(stderr, "zero point 0: %" PRId64 "\n",
+          mlirUniformQuantizedPerAxisTypeGetZeroPoint(perAxis, 0));
+  // CHECK: zero point 1: 120
+  fprintf(stderr, "zero point 1: %" PRId64 "\n",
+          mlirUniformQuantizedPerAxisTypeGetZeroPoint(perAxis, 1));
+  // CHECK: quantized dim: 1
+  fprintf(stderr, "quantized dim: %" PRId32 "\n",
+          mlirUniformQuantizedPerAxisTypeGetQuantizedDimension(perAxis));
+  // CHECK: fixed point: 0
+  fprintf(stderr, "fixed point: %d\n",
+          mlirUniformQuantizedPerAxisTypeIsFixedPoint(perAxis));
+
+  // CHECK: equal: 1
+  fprintf(stderr, "equal: %d\n", mlirTypeEqual(perAxis, perAxisParsed));
+  // CHECK: !quant.uniform<i8:f32:1, {2.000000e+02,9.987200e-01:120}>
+  mlirTypeDump(perAxis);
+  fprintf(stderr, "\n\n");
+}
+
+// CHECK-LABEL: testCalibratedType
+void testCalibratedType(MlirContext ctx) {
+  fprintf(stderr, "testCalibratedType\n");
+
+  MlirType calibratedParsed = mlirTypeParseGet(
+      ctx,
+      mlirStringRefCreateFromCString("!quant.calibrated<f32<-0.998:1.2321>>"));
+
+  MlirType f32 = mlirF32TypeGet(ctx);
+  MlirType calibrated = mlirCalibratedQuantizedTypeGet(f32, -0.998, 1.2321);
+
+  // CHECK: min: -0.998000
+  fprintf(stderr, "min: %lf\n", mlirCalibratedQuantizedTypeGetMin(calibrated));
+  // CHECK: max: 1.232100
+  fprintf(stderr, "max: %lf\n", mlirCalibratedQuantizedTypeGetMax(calibrated));
+
+  // CHECK: equal: 1
+  fprintf(stderr, "equal: %d\n", mlirTypeEqual(calibrated, calibratedParsed));
+  // CHECK: !quant.calibrated<f32<-0.998:1.232100e+00>>
+  mlirTypeDump(calibrated);
+  fprintf(stderr, "\n\n");
+}
+
+int main() {
+  MlirContext ctx = mlirContextCreate();
+  mlirDialectHandleRegisterDialect(mlirGetDialectHandle__quant__(), ctx);
+  testTypeHierarchy(ctx);
+  testAnyQuantizedType(ctx);
+  testUniformType(ctx);
+  testUniformPerAxisType(ctx);
+  testCalibratedType(ctx);
+  mlirContextDestroy(ctx);
+  return EXIT_SUCCESS;
+}
diff --git a/mlir/test/CMakeLists.txt b/mlir/test/CMakeLists.txt
--- a/mlir/test/CMakeLists.txt
+++ b/mlir/test/CMakeLists.txt
@@ -74,6 +74,7 @@
   mlir-capi-llvm-test
   mlir-capi-pass-test
   mlir-capi-sparse-tensor-test
+  mlir-capi-quant-test
   mlir-cpu-runner
   mlir-linalg-ods-yaml-gen
   mlir-lsp-server
diff --git a/mlir/test/lit.cfg.py b/mlir/test/lit.cfg.py
--- a/mlir/test/lit.cfg.py
+++ b/mlir/test/lit.cfg.py
@@ -65,6 +65,7 @@
     'mlir-capi-llvm-test',
     'mlir-capi-pass-test',
     'mlir-capi-sparse-tensor-test',
+    'mlir-capi-quant-test',
     'mlir-cpu-runner',
     'mlir-linalg-ods-yaml-gen',
     'mlir-reduce',
diff --git a/utils/bazel/llvm-project-overlay/mlir/BUILD.bazel b/utils/bazel/llvm-project-overlay/mlir/BUILD.bazel
--- a/utils/bazel/llvm-project-overlay/mlir/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/mlir/BUILD.bazel
@@ -496,6 +496,24 @@
     ],
 )
 
+mlir_c_api_cc_library(
+    name = "CAPIQuant",
+    srcs = [
+        "lib/CAPI/Dialect/Quant.cpp",
+    ],
+    hdrs = [
+        "include/mlir-c/Dialect/Quant.h",
+    ],
+    header_deps = [
+        ":CAPIIRHeaders",
+    ],
+    includes = ["include"],
+    deps = [
+        ":CAPIIR",
+        ":QuantOps",
+    ],
+)
+
 mlir_c_api_cc_library(
     name = "CAPIConversion",
     srcs = ["lib/CAPI/Conversion/Passes.cpp"],