diff --git a/src/oebuild/check_docker_tag.py b/src/oebuild/check_docker_tag.py
index 1080d165473926357bae79b37c1f855e20f8370f..a40979a727feef91390bd5b4a67bce6bf0bf3dac 100644
--- a/src/oebuild/check_docker_tag.py
+++ b/src/oebuild/check_docker_tag.py
@@ -39,10 +39,7 @@ class CheckDockerTag:
         oebuild_config = self.configure.parse_oebuild_config()
         docker_config = oebuild_config.docker
         tags = {}
-        for tag in docker_config.tag_map.values():
-            tags[tag] = True
-        for key in tags:
-            self.tag_list.append(key)
+        self.tag_list = list(set(docker_config.tag_map.values()))
 
     def get_tags(self,):
         '''