diff --git a/python/setup.py b/python/setup.py
index 47840c441..2968a5f29 100644
--- a/python/setup.py
+++ b/python/setup.py
@@ -40,7 +40,8 @@ setup(name="ray",
                         "colorama",
                         "psutil",
                         "redis",
-                        "cloudpickle >= 0.2.2"],
+                        "cloudpickle >= 0.2.2",
+                        "flatbuffers"],
       include_package_data=True,
       zip_safe=False,
       license="Apache 2.0")