diff --git a/.gitignore b/.gitignore
index db8a893a..e966c6b6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -53,6 +53,7 @@ src/google/protobuf/util/**/*.pb.h
 *.pyc
 *.egg-info
 *_pb2.py
+!python/google/protobuf/descriptor_pb2.py
 python/*.egg
 python/.eggs/
 python/.tox