diff --git a/deeprole/code/nn_train/requirements.txt b/deeprole/code/nn_train/requirements.txt
index 65f9146..2fc86a6 100644
--- a/deeprole/code/nn_train/requirements.txt
+++ b/deeprole/code/nn_train/requirements.txt
@@ -24,7 +24,7 @@ pbr==5.1.3
 pexpect==4.7.0
 pickleshare==0.7.5
 prompt-toolkit==1.0.16
-protobuf==3.7.1
+protobuf==3.15.0
 ptyprocess==0.6.0
 Pygments==2.3.1
 python-dateutil==2.8.0