diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2a7d805..65bd4db 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,7 +26,11 @@ set(CMAKE_AUTORCC ON)
 add_executable(gpsbabel)
 
 # Find the QtCore library
-find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+if(USE_QT6)
+  find_package(QT NAMES Qt6 COMPONENTS Core REQUIRED)
+else()
+  find_package(QT NAMES Qt5 COMPONENTS Core REQUIRED)
+endif()
 find_package(Qt${QT_VERSION_MAJOR} COMPONENTS Core REQUIRED)
 list(APPEND QT_LIBRARIES Qt${QT_VERSION_MAJOR}::Core)
 if(${Qt${QT_VERSION_MAJOR}Core_VERSION} VERSION_LESS 5.12)
diff --git a/gui/CMakeLists.txt b/gui/CMakeLists.txt
index 4c839c2..ac329dd 100644
--- a/gui/CMakeLists.txt
+++ b/gui/CMakeLists.txt
@@ -23,7 +23,11 @@ endif()
 add_executable(${TARGET} WIN32 MACOSX_BUNDLE)
 
 # Find the QtCore library
-find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+if(USE_QT6)
+  find_package(QT NAMES Qt6 COMPONENTS Core REQUIRED)
+else()
+  find_package(QT NAMES Qt5 COMPONENTS Core REQUIRED)
+endif()
 find_package(Qt${QT_VERSION_MAJOR} COMPONENTS Core Gui Network SerialPort Widgets Xml REQUIRED)
 list(APPEND QT_LIBRARIES Qt${QT_VERSION_MAJOR}::Core Qt${QT_VERSION_MAJOR}::Gui Qt${QT_VERSION_MAJOR}::Network Qt${QT_VERSION_MAJOR}::SerialPort Qt${QT_VERSION_MAJOR}::Widgets Qt${QT_VERSION_MAJOR}::Xml)
 if(${Qt${QT_VERSION_MAJOR}Core_VERSION} VERSION_LESS 5.12)