diff --git a/mlir/include/mlir/Dialect/Complex/IR/ComplexOps.td b/mlir/include/mlir/Dialect/Complex/IR/ComplexOps.td
--- a/mlir/include/mlir/Dialect/Complex/IR/ComplexOps.td
+++ b/mlir/include/mlir/Dialect/Complex/IR/ComplexOps.td
@@ -144,6 +144,7 @@
   let results = (outs AnyFloat:$imaginary);
 
   let assemblyFormat = "$complex attr-dict `:` type($complex)";
+  let hasFolder = 1;
 }
 
 //===----------------------------------------------------------------------===//
@@ -185,6 +186,7 @@
   let results = (outs AnyFloat:$real);
 
   let assemblyFormat = "$complex attr-dict `:` type($complex)";
+  let hasFolder = 1;
 }
 
 
diff --git a/mlir/lib/Dialect/Complex/IR/ComplexOps.cpp b/mlir/lib/Dialect/Complex/IR/ComplexOps.cpp
--- a/mlir/lib/Dialect/Complex/IR/ComplexOps.cpp
+++ b/mlir/lib/Dialect/Complex/IR/ComplexOps.cpp
@@ -17,3 +17,17 @@
 
 #define GET_OP_CLASSES
 #include "mlir/Dialect/Complex/IR/ComplexOps.cpp.inc"
+
+OpFoldResult ReOp::fold(ArrayRef<Attribute> operands) {
+  ArrayAttr arrayAttr = operands[0].dyn_cast_or_null<ArrayAttr>();
+  if (arrayAttr)
+    return arrayAttr[0];
+  return {};
+}
+
+OpFoldResult ImOp::fold(ArrayRef<Attribute> operands) {
+  ArrayAttr arrayAttr = operands[0].dyn_cast_or_null<ArrayAttr>();
+  if (arrayAttr)
+    return arrayAttr[1];
+  return {};
+}
diff --git a/mlir/test/Dialect/Complex/canonicalize.mlir b/mlir/test/Dialect/Complex/canonicalize.mlir
new file mode 100644
--- /dev/null
+++ b/mlir/test/Dialect/Complex/canonicalize.mlir
@@ -0,0 +1,19 @@
+// RUN: mlir-opt %s -canonicalize | FileCheck %s
+
+// CHECK-LABEL: func @real_of_const(
+func @real_of_const() -> f32 {
+  // CHECK: %[[CST:.*]] = constant 1.000000e+00 : f32
+  // CHECK-NEXT: return %[[CST]] : f32
+  %complex = constant [1.0 : f32, 0.0 : f32] : complex<f32>
+  %1 = complex.re %complex : complex<f32>
+  return %1 : f32
+}
+
+// CHECK-LABEL: func @imag_of_const(
+func @imag_of_const() -> f32 {
+  // CHECK: %[[CST:.*]] = constant 0.000000e+00 : f32
+  // CHECK-NEXT: return %[[CST]] : f32
+  %complex = constant [1.0 : f32, 0.0 : f32] : complex<f32>
+  %1 = complex.im %complex : complex<f32>
+  return %1 : f32
+}