diff --git a/requirements.txt b/requirements.txt
index 447a684..abf1c46 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -31,7 +31,7 @@ Keras==2.1.4
 Markdown==2.6.11
 MarkupSafe==1.0
 matplotlib==2.1.2
-mistune==0.8.3
+mistune==2.0.3
 -e git+https://github.com/openai/mujoco-py.git@6ac6ac203a875ef35b1505827264cadccbfd9f05#egg=mujoco_py
 nbconvert==5.3.1
 nbformat==4.4.0