diff --git a/CMakeLists.txt b/CMakeLists.txt
index acc727019..556d5cd31 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -627,7 +627,7 @@ if(WIN32)
     set(PYTHON_PACKAGES_PATH "${PYTHON_PATH}/Lib/site-packages")
 endif()
 
-IF (${PYTHON_VERSION_MAJOR_MINOR} VERSION_GREATER 2.5)
+IF ("${PYTHON_VERSION_MAJOR_MINOR}" VERSION_GREATER 2.5)
     SET(PYTHON_EXECUTABLE ${PYTHON_EXECUTABLE} -B)
 ENDIF()