diff --git a/gateway/platforms/feishu.py b/gateway/platforms/feishu.py
index 01b1c3a14b..0b55e2b786 100644
--- a/gateway/platforms/feishu.py
+++ b/gateway/platforms/feishu.py
@@ -1172,6 +1172,7 @@ class FeishuAdapter(BasePlatformAdapter):
         )
 
     def _apply_settings(self, settings: FeishuAdapterSettings) -> None:
+        self._last_inbound_message_ids: dict = {}  # chat_id -> message_id
         self._app_id = settings.app_id
         self._app_secret = settings.app_secret
         self._domain_name = settings.domain_name
@@ -2186,6 +2187,9 @@ class FeishuAdapter(BasePlatformAdapter):
         )
 
         chat_id = getattr(message, "chat_id", "") or ""
+        # Track last inbound message_id per chat for auto-thread reply
+        if chat_id and message_id:
+            self._last_inbound_message_ids[chat_id] = message_id
         chat_info = await self.get_chat_info(chat_id)
         sender_profile = await self._resolve_sender_profile(sender_id)
         source = self.build_source(
@@ -3272,7 +3276,11 @@ class FeishuAdapter(BasePlatformAdapter):
         reply_to: Optional[str],
         metadata: Optional[Dict[str, Any]],
     ) -> Any:
-        reply_in_thread = bool((metadata or {}).get("thread_id"))
+        _auto_thread = os.getenv("FEISHU_AUTO_THREAD", "false").lower() in ("true", "1", "yes")
+        reply_in_thread = bool((metadata or {}).get("thread_id")) or _auto_thread
+        # When auto_thread is on and no reply_to, use last inbound message_id
+        if _auto_thread and not reply_to:
+            reply_to = self._last_inbound_message_ids.get(chat_id)
         if reply_to:
             body = self._build_reply_message_body(
                 content=payload,
diff --git a/gateway/run.py b/gateway/run.py
index 2eb745f92b..89b9ece4aa 100644
--- a/gateway/run.py
+++ b/gateway/run.py
@@ -7840,11 +7840,14 @@ class GatewayRunner:
                         buffer_threshold=_scfg.buffer_threshold,
                         cursor=_effective_cursor,
                     )
+                    _feishu_auto_thread = os.getenv("FEISHU_AUTO_THREAD", "false").lower() in ("true", "1", "yes")
+                    _sc_reply_to = event_message_id if (_feishu_auto_thread and source.platform == Platform.FEISHU) else None
                     _stream_consumer = GatewayStreamConsumer(
                         adapter=_adapter,
                         chat_id=source.chat_id,
                         config=_consumer_cfg,
                         metadata=_thread_metadata,
+                        reply_to=_sc_reply_to,
                     )
             except Exception as _sc_err:
                 logger.debug("Proxy: could not set up stream consumer: %s", _sc_err)
@@ -8406,11 +8409,14 @@ class GatewayRunner:
                             buffer_threshold=_scfg.buffer_threshold,
                             cursor=_effective_cursor,
                         )
+                        _feishu_auto_thread2 = os.getenv("FEISHU_AUTO_THREAD", "false").lower() in ("true", "1", "yes")
+                        _sc_reply_to2 = event_message_id if (_feishu_auto_thread2 and source.platform == Platform.FEISHU) else None
                         _stream_consumer = GatewayStreamConsumer(
                             adapter=_adapter,
                             chat_id=source.chat_id,
                             config=_consumer_cfg,
                             metadata={"thread_id": _progress_thread_id} if _progress_thread_id else None,
+                            reply_to=_sc_reply_to2,
                         )
                         if _want_stream_deltas:
                             _stream_delta_cb = _stream_consumer.on_delta
diff --git a/gateway/stream_consumer.py b/gateway/stream_consumer.py
index e6d96c802d..d584b196b6 100644
--- a/gateway/stream_consumer.py
+++ b/gateway/stream_consumer.py
@@ -82,6 +82,7 @@ class GatewayStreamConsumer:
         chat_id: str,
         config: Optional[StreamConsumerConfig] = None,
         metadata: Optional[dict] = None,
+        reply_to: Optional[str] = None,
     ):
         self.adapter = adapter
         self.chat_id = chat_id
@@ -89,7 +90,7 @@ class GatewayStreamConsumer:
         self.metadata = metadata
         self._queue: queue.Queue = queue.Queue()
         self._accumulated = ""
-        self._message_id: Optional[str] = None
+        self._message_id: Optional[str] = reply_to
         self._already_sent = False
         self._edit_supported = True  # Disabled when progressive edits are no longer usable
         self._last_edit_time = 0.0