diff --git a/bitbake/lib/bb/utils.py b/bitbake/lib/bb/utils.py
index 128b3ab570..8d614fe236 100644
--- a/bitbake/lib/bb/utils.py
+++ b/bitbake/lib/bb/utils.py
@@ -1733,7 +1733,7 @@ def environment(**envvars):
         for var in envvars:
             if var in backup:
                 os.environ[var] = backup[var]
-            else:
+            elif var in os.environ:
                 del os.environ[var]
 
 def is_local_uid(uid=''):