diff --git a/src/python/grpcio/setup.py b/src/python/grpcio/setup.py
index a948ca1fac6d819cb7ebc5d38ff0bb3f2aa7a63f..b8a98c3d859f2243bdcc6305d14edd74dc519f86 100644
--- a/src/python/grpcio/setup.py
+++ b/src/python/grpcio/setup.py
@@ -163,7 +163,7 @@ else:
 
 setuptools.setup(
     name='grpcio',
-    version='0.11.0b2',
+    version='0.12.0b0',
     ext_modules=CYTHON_EXTENSION_MODULES,
     packages=list(PACKAGES),
     package_dir=PACKAGE_DIRECTORIES,