diff --git a/runconfig/merge.go b/runconfig/merge.go
index 7d4cde06c..df53ef964 100644
--- a/runconfig/merge.go
+++ b/runconfig/merge.go
@@ -33,6 +33,7 @@ func Merge(userConf, imageConf *Config) error {
 				userEnvKey := strings.Split(userEnv, "=")[0]
 				if imageEnvKey == userEnvKey {
 					found = true
+					break
 				}
 			}
 			if !found {