diff --git a/requirements_dev.txt b/requirements_dev.txt
index ea164a7f..132dd069 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -5,7 +5,7 @@ watchdog==0.8.3
 flake8==3.5.0
 tox==2.9.1
 coverage==4.5.1
-Sphinx==1.7.7
+Sphinx==8.1.1
 cryptography==2.3.1
 pytest==4.5.0
 pytest-runner==3.0