diff --git a/requirements.txt b/requirements.txt
index 0936390..63bd173 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -35,7 +35,7 @@ korean-lunar-calendar==0.2.1
 LunarCalendar==0.0.9
 MarkupSafe==1.1.1
 matplotlib==3.3.1
-mistune==0.8.4
+mistune==2.0.3
 mpmath==1.1.0
 nbconvert==5.6.1
 nbformat==5.0.7