diff --git a/requirements.txt b/requirements.txt
index ff400b03a..c8f980af2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -14,6 +14,6 @@ regex==2017.4.5
 ftfy>=4.4.2,<5.0.0
 pytest>=3.0.6,<4.0.0
 mock>=2.0.0,<3.0.0
-msgpack-python
+msgpack-python==0.5.4
 msgpack-numpy==0.4.1
 html5lib==1.0b8
diff --git a/setup.py b/setup.py
index 7c26a7491..37bd3d4a2 100755
--- a/setup.py
+++ b/setup.py
@@ -199,7 +199,7 @@ def setup_package():
                 'requests>=2.13.0,<3.0.0',
                 'regex==2017.4.5',
                 'ftfy>=4.4.2,<5.0.0',
-                'msgpack-python',
+                'msgpack-python==0.5.4',
                 'msgpack-numpy==0.4.1'],
             classifiers=[
                 'Development Status :: 5 - Production/Stable',