diff --git a/src/3rdparty/CMakeLists.txt b/src/3rdparty/CMakeLists.txt
index 437451e86..2080b8da4 100644
--- a/src/3rdparty/CMakeLists.txt
+++ b/src/3rdparty/CMakeLists.txt
@@ -60,6 +60,8 @@ if(BUILD_QXLSX)
 
     get_target_property(QXLSX_VERSION QXlsx VERSION)
     message(STATUS "QXlsx VERSION ${QXLSX_VERSION}")
+endif()
+if(BUILD_QXLSX OR QXLSX_FOUND)
     target_compile_definitions(labplotlib PRIVATE QXLSX_VERSION_STRING=\"${QXLSX_VERSION}\")
 endif()