diff --git a/paddle/setup.py.in b/paddle/setup.py.in
index 549baa086d5aa49498a8fa3bcdb0bd16b89a35dc..0b62436a7f81682d5279c3b307ac1abf09eafffb 100644
--- a/paddle/setup.py.in
+++ b/paddle/setup.py.in
@@ -21,6 +21,7 @@ setup(name="py_paddle",
       include_package_data=True,
       package_data={'py_paddle':['*.py','_swig_paddle.so']},
       install_requires = [
+        'nltk>=3.2.2',
         'numpy>=1.8.0',      # The numpy is required.
         'protobuf>=${PROTOBUF_VERSION}'    # The paddle protobuf version
       ],