diff --git a/scripting/python_scripting.cpp b/scripting/python_scripting.cpp
index 748c2a9c83..8bf3ac8b06 100644
--- a/scripting/python_scripting.cpp
+++ b/scripting/python_scripting.cpp
@@ -113,7 +113,7 @@ bool SCRIPTING::scriptingSetup()
     pyHome.Normalize();
 
     // MUST be called before Py_Initialize so it will to create valid default lib paths
-    if( !wxGetEnv( wxT( "KICAD_RUN_FROM_BUILD_DIR" ), nullptr ) )
+    if( !wxGetEnv( wxT( "KICAD_USE_EXTERNAL_PYTHONHOME" ), nullptr ) )
     {
         Py_SetPythonHome( pyHome.GetFullPath().c_str() );
     }