diff --git a/tools/dockerfile/test/php7_jessie_x64/Dockerfile b/tools/dockerfile/test/php7_jessie_x64/Dockerfile
index 221338956ef..c0b394e5d0c 100644
--- a/tools/dockerfile/test/php7_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/php7_jessie_x64/Dockerfile
@@ -88,7 +88,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.0.0a2 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.0.0a2
 
 # Prepare ccache
 RUN ln -s /usr/bin/ccache /usr/local/bin/gcc