diff --git a/src/osx/utils_osx.cpp b/src/osx/utils_osx.cpp
index 1f09af498f..0cd8cda713 100644
--- a/src/osx/utils_osx.cpp
+++ b/src/osx/utils_osx.cpp
@@ -90,6 +90,7 @@ int wxDisplayDepth()
             theDepth = 32; // some reasonable default
 
         CFRelease(encoding);
+        CGDisplayModeRelease(currentMode);
     }
     else
 #endif