diff --git a/build_scripts/OSX/MacOS_X_InstallGuide.md b/build_scripts/OSX/MacOS_X_InstallGuide.md
index df28ce21b..9e2089baf 100644
--- a/build_scripts/OSX/MacOS_X_InstallGuide.md
+++ b/build_scripts/OSX/MacOS_X_InstallGuide.md
@@ -31,6 +31,7 @@ For VOIP Plugin:
 
        $ sudo port install speex-devel
        $ sudo port install opencv
+       $ sudo port install ffmpeg
 
 Get Your OSX SDK if missing: [MacOSX-SDKs](https://github.com/phracker/MacOSX-SDKs)