diff --git a/mlir/include/mlir/TableGen/Predicate.h b/mlir/include/mlir/TableGen/Predicate.h
index a9afafcc660d..49f7ebcfe52a 100644
--- a/mlir/include/mlir/TableGen/Predicate.h
+++ b/mlir/include/mlir/TableGen/Predicate.h
@@ -24,6 +24,7 @@
 
 #include "mlir/Support/LLVM.h"
 
+#include <string>
 #include <vector>
 
 namespace llvm {