diff --git a/docs/requirements.txt b/docs/requirements.txt
index 730e2f0..12c06ae 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,3 +1,3 @@
-Sphinx==1.8.1
+Sphinx==2.1.0
 sphinx-autobuild==0.7.1
 sphinx-rtd-theme==0.4.2