diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index 63cf0a4c74c36e7b44d57630eb447e75b35df795..952898d74a2c8cf795ab88216aaaeb7efcc99f51 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -188,6 +188,7 @@ CORE_SOURCE_FILES = [
   'src/core/surface/server.c',
   'src/core/surface/server_chttp2.c',
   'src/core/surface/server_create.c',
+  'src/core/surface/validate_metadata.c',
   'src/core/surface/version.c',
   'src/core/transport/byte_stream.c',
   'src/core/transport/chttp2/alpn.c',