diff --git a/CMakeLists.txt b/CMakeLists.txt
index ac77840a..9371c6ab 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -205,9 +205,7 @@ if(WIN32)
 endif()
 
 if(APPLE)
-    if(NOT CMAKE_OSX_DEPLOYMENT_TARGET)
-        set(CMAKE_OSX_DEPLOYMENT_TARGET "10.13")
-    endif()
+    set(CMAKE_OSX_DEPLOYMENT_TARGET "10.13")
     MESSAGE(STATUS "CMAKE_OSX_DEPLOYMENT_TARGET: " ${CMAKE_OSX_DEPLOYMENT_TARGET})
 
     set(MACOSX_BUNDLE_GUI_IDENTIFIER ${IDENTIFIER})