diff --git a/tools/distrib/run_clang_tidy.py b/tools/distrib/run_clang_tidy.py
index 337e6b43c86..3dbce0b2e67 100755
--- a/tools/distrib/run_clang_tidy.py
+++ b/tools/distrib/run_clang_tidy.py
@@ -28,6 +28,7 @@ GRPC_CHECKS = [
     'modernize-use-nullptr',
     'google-build-namespaces',
     'google-build-explicit-make-pair',
+    'readability-function-size',
 ]
 
 extra_args = [