diff --git a/src/openrct2/core/Diagnostics.cpp b/src/openrct2/core/Diagnostics.cpp
index a56b6bcae3..3cc20bad96 100644
--- a/src/openrct2/core/Diagnostics.cpp
+++ b/src/openrct2/core/Diagnostics.cpp
@@ -8,7 +8,6 @@
  *****************************************************************************/
 
 #if defined(DEBUG) && defined(_WIN32)
-#    define WIN32_LEAN_AND_MEAN
 #    include <windows.h>
 #endif
 
diff --git a/src/openrct2/rct12/SawyerChunkReader.cpp b/src/openrct2/rct12/SawyerChunkReader.cpp
index 7b0f5b12b0..81339d93fa 100644
--- a/src/openrct2/rct12/SawyerChunkReader.cpp
+++ b/src/openrct2/rct12/SawyerChunkReader.cpp
@@ -15,7 +15,6 @@
 // memory on a special debug heap and then initialises all the memory to 0xCC.
 #if defined(_WIN32) && defined(DEBUG)
 #    define __USE_HEAP_ALLOC__
-#    define WIN32_LEAN_AND_MEAN
 #    include <windows.h>
 #endif