diff --git a/requirements.txt b/requirements.txt
index cd19cc9..9dae09a 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,6 +6,6 @@ pbr!=2.1.0,>2.0.0  # Apache-2.0
 
 openstackdocstheme>=1.18.1 # Apache-2.0
 sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD
-sphinxcontrib-blockdiag==1.5.4 # BSD
+sphinxcontrib-blockdiag==2.0.0 # BSD
 
 yasfb>=0.5.1