diff --git a/pip-requirements.txt b/pip-requirements.txt
index 315ace5..b68cf5d 100644
--- a/pip-requirements.txt
+++ b/pip-requirements.txt
@@ -84,7 +84,7 @@ plac==0.9.6
 polyglot==16.7.4
 preshed==1.0.0
 prompt-toolkit==1.0.14
-protobuf==3.3.0
+protobuf==3.15.0
 ptyprocess==0.5.1
 pyasn1==0.1.9
 pyasn1-modules==0.0.7