diff --git a/flang/lib/Lower/IntrinsicCall.cpp b/flang/lib/Lower/IntrinsicCall.cpp
--- a/flang/lib/Lower/IntrinsicCall.cpp
+++ b/flang/lib/Lower/IntrinsicCall.cpp
@@ -454,6 +454,7 @@
   mlir::Value genIand(mlir::Type, llvm::ArrayRef<mlir::Value>);
   mlir::Value genIbits(mlir::Type, llvm::ArrayRef<mlir::Value>);
   mlir::Value genIbset(mlir::Type, llvm::ArrayRef<mlir::Value>);
+  mlir::Value genIeor(mlir::Type, llvm::ArrayRef<mlir::Value>);
   fir::ExtendedValue genLbound(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
   fir::ExtendedValue genNull(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
   fir::ExtendedValue genLen(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
@@ -611,6 +612,7 @@
     {"iand", &I::genIand},
     {"ibits", &I::genIbits},
     {"ibset", &I::genIbset},
+    {"ieor", &I::genIeor},
     {"len",
      &I::genLen,
      {{{"string", asInquired}, {"kind", asValue}}},
@@ -1747,6 +1749,13 @@
   return builder.create<mlir::arith::OrIOp>(loc, args[0], mask);
 }
 
+// IEOR
+mlir::Value IntrinsicLibrary::genIeor(mlir::Type resultType,
+                                      llvm::ArrayRef<mlir::Value> args) {
+  assert(args.size() == 2);
+  return builder.create<mlir::arith::XOrIOp>(loc, args[0], args[1]);
+}
+
 // LEN
 // Note that this is only used for an unrestricted intrinsic LEN call.
 // Other uses of LEN are rewritten as descriptor inquiries by the front-end.
diff --git a/flang/test/Lower/Intrinsics/ieor.f90 b/flang/test/Lower/Intrinsics/ieor.f90
new file mode 100644
--- /dev/null
+++ b/flang/test/Lower/Intrinsics/ieor.f90
@@ -0,0 +1,9 @@
+! RUN: bbc -emit-fir %s -o - | FileCheck %s
+
+! CHECK-LABEL: ieor_test
+subroutine ieor_test(a, b)
+  integer :: a, b
+  print *, ieor(a, b)
+  ! CHECK: %{{[0-9]+}} = arith.xori %{{[0-9]+}}, %{{[0-9]+}} : i{{(8|16|32|64|128)}}
+end subroutine ieor_test
+