diff --git a/requirements.txt b/requirements.txt
index 48e03b8b..7543d867 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,3 +2,4 @@ cython>=0.17
 matplotlib>=1.0
 numpy>=1.6
 six>=1.3.0
+networkx>=1.8.0