diff --git a/python/ray/__init__.py b/python/ray/__init__.py
index 3d243c322..5336dd3a0 100644
--- a/python/ray/__init__.py
+++ b/python/ray/__init__.py
@@ -95,7 +95,7 @@ from ray.actor import method  # noqa: E402
 from ray.runtime_context import _get_runtime_context  # noqa: E402
 
 # Ray version string.
-__version__ = "0.7.0.dev0"
+__version__ = "0.6.4"
 
 __all__ = [
     "LOCAL_MODE",