diff --git a/requirements.txt b/requirements.txt
index 165c560..e0ba9ef 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,7 +8,7 @@ Keras-Preprocessing==1.0.5
 Markdown==3.0.1
 numpy==1.15.4
 Pillow==6.2.0
-protobuf==3.6.1
+protobuf==3.18.3
 pytest==4.0.1
 scikit-learn==0.20.0
 scipy==1.1.0