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
@@ -222,6 +222,31 @@
   let results = (outs Complex<AnyFloat>:$result);
 }
 
+//===----------------------------------------------------------------------===//
+// Expm1Op
+//===----------------------------------------------------------------------===//
+
+def Expm1Op : ComplexUnaryOp<"expm1", [SameOperandsAndResultType]> {
+  let summary = "computes exponential of a complex number minus 1";
+  let description = [{
+    Syntax:
+
+    ```
+    operation ::= ssa-id `=` `complex.expm1` ssa-use `:` type
+    ```
+
+    complex.expm1(x) := complex.exp(x) - 1
+
+    Example:
+
+    ```mlir
+    %a = complex.expm1 %b : complex<f32>
+    ```
+  }];
+
+  let results = (outs Complex<AnyFloat>:$result);
+}
+
 //===----------------------------------------------------------------------===//
 // ImOp
 //===----------------------------------------------------------------------===//
diff --git a/mlir/test/Dialect/Complex/ops.mlir b/mlir/test/Dialect/Complex/ops.mlir
--- a/mlir/test/Dialect/Complex/ops.mlir
+++ b/mlir/test/Dialect/Complex/ops.mlir
@@ -38,6 +38,9 @@
   // CHECK: complex.exp %[[C]] : complex<f32>
   %exp = complex.exp %complex : complex<f32>
 
+  // CHECK: complex.expm1 %[[C]] : complex<f32>
+  %expm1 = complex.expm1 %complex : complex<f32>
+
   // CHECK: complex.log %[[C]] : complex<f32>
   %log = complex.log %complex : complex<f32>