diff --git a/docs/requirements.txt b/docs/requirements.txt
index 0dbfecb..092795d 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,3 +1,3 @@
-sphinx>=1.3
+sphinx==1.8.3
 sphinx-rtd-theme==0.4.2
 -e .