diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9f7102d3cc..646cd86dcd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -580,6 +580,9 @@ function(protobuf_generate_grpc_cpp_with_import_path_correction FILE_LOCATION IM
     message(SEND_ERROR "Error: PROTOBUF_GENERATE_GRPC_CPP() called without any proto files")
     return()
   endif()
+  if(NOT EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/${FILE_LOCATION}")
+    return()
+  endif()
 
   # Sets the include path for ProtoBuf files
   set(_protobuf_include_path -I . -I ${_gRPC_PROTOBUF_WELLKNOWN_INCLUDE_DIR})