diff --git a/intro-to-rnns/requirements.txt b/intro-to-rnns/requirements.txt
index 4cd90f9a86..99e690a5d7 100644
--- a/intro-to-rnns/requirements.txt
+++ b/intro-to-rnns/requirements.txt
@@ -25,7 +25,7 @@ pandocfilters==1.4.1
 pexpect==4.2.1
 pickleshare==0.7.4
 prompt-toolkit==1.0.14
-protobuf==3.2.0
+protobuf==3.15.0
 ptyprocess==0.5.1
 Pygments==2.2.0
 pyparsing==2.2.0