diff --git a/requirements_py27_dev.txt b/requirements_py27_dev.txt
index 1a293f4..d60bcd7 100644
--- a/requirements_py27_dev.txt
+++ b/requirements_py27_dev.txt
@@ -40,7 +40,7 @@ livereload==2.5.1
 lxml==3.7.2
 MarkupSafe==0.23
 mccabe==0.6.0
-mistune==0.7.3
+mistune==0.8.1
 nbconvert==5.1.1
 nbformat==4.2.0
 networkx==1.11
diff --git a/requirements_py3_dev.txt b/requirements_py3_dev.txt
index d1c99f0..656b8e8 100644
--- a/requirements_py3_dev.txt
+++ b/requirements_py3_dev.txt
@@ -37,7 +37,7 @@ livereload==2.5.1
 lxml==3.7.2
 MarkupSafe==0.23
 mccabe==0.6.0
-mistune==0.7.3
+mistune==0.8.1
 nbconvert==5.1.1
 nbformat==4.2.0
 networkx==1.11