diff --git a/swift/rlhf_trainers/gkd_loss.py b/swift/rlhf_trainers/gkd_loss.py
index 2e749e691c..6d67d41bbb 100644
--- a/swift/rlhf_trainers/gkd_loss.py
+++ b/swift/rlhf_trainers/gkd_loss.py
@@ -265,6 +265,11 @@ def gkd_loss(
 def build_opsd_teacher_data(inputs, strip_assistant=False):
     """Build teacher data for OPSD by replacing the last user message with teacher_prompt.
 
+    teacher_prompt supports two formats:
+        1. str: Used only as the user content for the teacher, replacing the last user message.
+        2. list[dict]: A complete list of messages (including system/user/assistant),
+           which directly replaces the teacher's messages (retaining the assistant from the original data as the response).
+
     Args:
         inputs: list of data dicts, each may contain 'teacher_prompt'
         strip_assistant: if True, remove trailing assistant message before replacement
@@ -277,13 +282,32 @@ def build_opsd_teacher_data(inputs, strip_assistant=False):
     result = []
     for data in inputs:
         item = {k: v for k, v in data.items() if k != 'teacher_prompt'}
-        messages = [dict(m) for m in data.get('messages', [])]
-        if strip_assistant and messages and messages[-1]['role'] == 'assistant':
-            messages.pop()
-        for msg in reversed(messages):
-            if msg['role'] == 'user':
-                msg['content'] = data['teacher_prompt']
-                break
-        item['messages'] = messages
+        tp = data['teacher_prompt']
+
+        if isinstance(tp, list):
+            # teacher_prompt is already a complete list of messages (including system/user/optional assistant)
+            teacher_messages = [dict(m) for m in tp]
+            # Fallback: If teacher_prompt does not end with an assistant message, fetch it from the original messages
+            if (not teacher_messages) or teacher_messages[-1].get('role') != 'assistant':
+                orig = data.get('messages', [])
+                for m in reversed(orig):
+                    if m.get('role') == 'assistant':
+                        teacher_messages.append(dict(m))
+                        break
+            if strip_assistant and teacher_messages and teacher_messages[-1].get('role') == 'assistant':
+                teacher_messages.pop()
+            item['messages'] = teacher_messages
+        else:
+            # teacher_prompt is a string: Replace the content of the last user message in the original messages
+            messages = [dict(m) for m in data.get('messages', [])]
+            if strip_assistant and messages and messages[-1]['role'] == 'assistant':
+                messages.pop()
+            for msg in reversed(messages):
+                if msg['role'] == 'user':
+                    msg['content'] = tp
+                    break
+            item['messages'] = messages
+
         result.append(item)
     return result
+