diff --git a/source/tutorial/install-mongodb-on-os-x.txt b/source/tutorial/install-mongodb-on-os-x.txt
index 292354a0e35..bd7743cb4c8 100644
--- a/source/tutorial/install-mongodb-on-os-x.txt
+++ b/source/tutorial/install-mongodb-on-os-x.txt
@@ -7,7 +7,7 @@ Install MongoDB on OS X
 Overview
 --------
 
-Use this tutorial to install MongoDB on on OS X systems.
+Use this tutorial to install MongoDB on OS X systems.
 
 .. admonition:: Platform Support