diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 0955b27..e648982 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -264,7 +264,7 @@ set_target_properties(${targetname} PROPERTIES
     SOVERSION "${LIBQGPGME_SOVERSION}"
 )
 
-target_include_directories(${targetname} INTERFACE "$<INSTALL_INTERFACE:include/qgpgme-qt${QT_MAJOR_VERSION}>")
+target_include_directories(${targetname} INTERFACE "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/qgpgme-qt${QT_MAJOR_VERSION}>")
 
 if (${QT_MAJOR_VERSION} EQUAL 6)
     set(config_suffix Qt6)