diff --git a/README.md b/README.md
index 53ac523..d5d0c17 100644
--- a/README.md
+++ b/README.md
@@ -105,6 +105,7 @@ typings file will also be generated for the protobuf messages and service stub.
 `import_style=typescript`: (Experimental) The service stub will be generated
 in TypeScript.
 
+**Note: `commonjs+dts` and `typescript` only works with `--grpc-web_out=` import style.**
 
 ### Wire Format Mode