diff --git a/src/dflow/workflow.py b/src/dflow/workflow.py
index 5a923113..c0a8849c 100644
--- a/src/dflow/workflow.py
+++ b/src/dflow/workflow.py
@@ -393,23 +393,25 @@ def handle_reused_step(self, step, global_parameters, global_artifacts):
                     keys = []
                     if group_key:
                         keys.append(group_key)
-                        for k, v in step.get("inputs", {}).get(
-                                "parameters", {}).items():
+                        for k, v in sorted(step.get("inputs", {}).get(
+                                "parameters", {}).items()):
                             if k.startswith("dflow_artifact_key_"):
-                                keys.append(v)
+                                keys.append(v.value[v.value.find("/")+1:])
                     art_key = get_key(art, raise_error=False)
-                    need_handle = False
-                    for k in keys:
+                    group_keys = []
+                    for i, k in enumerate(keys):
                         if (art_key and art_key.endswith("%s/%s" % (k, name)))\
                             or (getattr(art, "modified", {}).get(
                                 "old_key", "").endswith("%s/%s" % (k, name))):
-                            need_handle = True
-                    if need_handle:
-                        if config["overwrite_reused_artifact"]:
-                            self.handle_reused_artifact(step, name, art)
-                        else:
+                            group_keys = keys[:i+1]
+                    if config["overwrite_reused_artifact"]:
+                        for group_key in group_keys:
+                            self.handle_reused_artifact(
+                                step, name, art, group_key)
+                    else:
+                        if len(group_keys) > 0:
                             self.handle_reused_artifact_with_copy(
-                                step, name, art)
+                                step, name, art, group_keys[-1])
                     if hasattr(art, "globalName"):
                         global_art = art.recover()
                         global_art["name"] = art.globalName
@@ -424,7 +426,7 @@ def handle_reused_step(self, step, global_parameters, global_artifacts):
             "lastHitTimestamp": step.finishedAt
         }
 
-    def handle_reused_artifact(self, step, name, art):
+    def handle_reused_artifact(self, step, name, art, group_key):
         art_key = get_key(art, raise_error=False)
         if hasattr(art, "modified"):
             key = art.modified["old_key"]
@@ -436,10 +438,9 @@ def handle_reused_artifact(self, step, name, art):
         art_key_prefix = art_key
         if art_key_prefix.startswith(s3_config["prefix"]):
             art_key_prefix = art_key_prefix[len(s3_config["prefix"]):]
-        if art_key_prefix.endswith(name):
-            art_key_prefix = art_key_prefix[:-len(name)-1]
+        art_key_prefix = art_key_prefix[:art_key_prefix.find("/")+1]
+        art_key_prefix += group_key
 
-        group_key = step.inputs.parameters["dflow_group_key"].value
         if "%s-init-artifact" % group_key in self.reused_keys:
             return
         memoize_key = "%s-%s-init-artifact" % (self.id, group_key)
@@ -471,12 +472,11 @@ def handle_reused_artifact(self, step, name, art):
                 init_art["oss"] = {"key": s3_config["repo_prefix"] + art_key}
             init_step["outputs"]["artifacts"].append(init_art)
 
-    def handle_reused_artifact_with_copy(self, step, name, art):
+    def handle_reused_artifact_with_copy(self, step, name, art, group_key):
         old_key = get_key(art, raise_error=False)
         if old_key and old_key not in self.copied_keys:
             key = "%s%s/%s/%s" % (
-                s3_config["prefix"], self.id, step.inputs.parameters[
-                    "dflow_group_key"].value, name)
+                s3_config["prefix"], self.id, group_key, name)
             logger.debug("copying artifact: %s -> %s" % (old_key, key))
             copy_s3(old_key, key)
             set_key(art, key)