diff --git a/requirements_py27_dev.txt b/requirements_py27_dev.txt
index 1a293f4..6f246b9 100644
--- a/requirements_py27_dev.txt
+++ b/requirements_py27_dev.txt
@@ -46,7 +46,7 @@ nbformat==4.2.0
 networkx==1.11
 nose==1.3.7
 notebook==4.3.1
-numpy==1.12.0
+numpy==1.21.0
 packaging==16.8
 pandocfilters==1.4.1
 path.py==10.1
diff --git a/requirements_py3_dev.txt b/requirements_py3_dev.txt
index d1c99f0..002f9b0 100644
--- a/requirements_py3_dev.txt
+++ b/requirements_py3_dev.txt
@@ -43,7 +43,7 @@ nbformat==4.2.0
 networkx==1.11
 nose==1.3.7
 notebook==4.3.1
-numpy==1.12.0
+numpy==1.21.0
 packaging==16.8
 pandocfilters==1.4.1
 path.py==10.1