diff --git a/CMakeLists.txt b/CMakeLists.txt
index 74fab32e..6167ed54 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -529,13 +529,15 @@ if (ISLE_BUILD_APP)
       ISLE/3ds/config.cpp
     )
   endif()
-  add_custom_command(
-    OUTPUT ${CMAKE_SOURCE_DIR}/ISLE/res/arrow_bmp.h ${CMAKE_SOURCE_DIR}/ISLE/res/busy_bmp.h ${CMAKE_SOURCE_DIR}/ISLE/res/no_bmp.h
-    COMMAND ${Python3_EXECUTABLE} tools/png2h.py ISLE/res/arrow.png ISLE/res/busy.png ISLE/res/no.png
-    DEPENDS ISLE/res/arrow.png ISLE/res/busy.png ISLE/res/no.png
-    WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
-  )
-  add_custom_target(generate_header ALL DEPENDS ${CMAKE_SOURCE_DIR}/ISLE/res/arrow_bmp.h ${CMAKE_SOURCE_DIR}/ISLE/res/busy_bmp.h ${CMAKE_SOURCE_DIR}/ISLE/res/no_bmp.h)
+  if(Python3_FOUND)
+    add_custom_command(
+      OUTPUT ${CMAKE_SOURCE_DIR}/ISLE/res/arrow_bmp.h ${CMAKE_SOURCE_DIR}/ISLE/res/busy_bmp.h ${CMAKE_SOURCE_DIR}/ISLE/res/no_bmp.h
+      COMMAND ${Python3_EXECUTABLE} tools/png2h.py ISLE/res/arrow.png ISLE/res/busy.png ISLE/res/no.png
+      DEPENDS ISLE/res/arrow.png ISLE/res/busy.png ISLE/res/no.png
+      WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
+    )
+    add_custom_target(generate_header ALL DEPENDS ${CMAKE_SOURCE_DIR}/ISLE/res/arrow_bmp.h ${CMAKE_SOURCE_DIR}/ISLE/res/busy_bmp.h ${CMAKE_SOURCE_DIR}/ISLE/res/no_bmp.h)
+  endif()
 endif()
 
 if (ISLE_BUILD_CONFIG)