diff --git a/include/boost/python/detail/wrap_python.hpp b/include/boost/python/detail/wrap_python.hpp
index 037e4bf2ec..056db48369 100644
--- a/include/boost/python/detail/wrap_python.hpp
+++ b/include/boost/python/detail/wrap_python.hpp
@@ -206,7 +206,6 @@ typedef int pid_t;
 
 #ifdef DEBUG_UNDEFINED_FROM_WRAP_PYTHON_H
 # undef DEBUG_UNDEFINED_FROM_WRAP_PYTHON_H
-# define _DEBUG
 # ifdef _CRT_NOFORCE_MANIFEST_DEFINED_FROM_WRAP_PYTHON_H
 #  undef _CRT_NOFORCE_MANIFEST_DEFINED_FROM_WRAP_PYTHON_H
 #  undef _CRT_NOFORCE_MANIFEST