diff --git a/requirements.txt b/requirements.txt
index ab491ed..8846399 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -24,7 +24,7 @@ kiwisolver==1.1.0
 MarkupSafe==1.1.1
 matplotlib==3.1.2
 mecab-python3==0.996.2
-mistune==0.8.4
+mistune==2.0.3
 more-itertools==8.0.0
 nbconvert==5.6.1
 nbformat==4.4.0