diff --git a/gateway/platforms/qqbot/adapter.py b/gateway/platforms/qqbot/adapter.py
index 5b4a396ed2f..9532662131d 100644
--- a/gateway/platforms/qqbot/adapter.py
+++ b/gateway/platforms/qqbot/adapter.py
@@ -681,6 +681,12 @@ class QQAdapter(BasePlatformAdapter):
         """Read WebSocket frames until connection closes."""
         if not self._ws:
             raise RuntimeError("WebSocket not connected")
+        if self._ws.closed:
+            # A closed-but-non-None ws makes the while-condition false on entry,
+            # so this would return normally — which _listen_loop treats as a
+            # clean read and immediately retries with backoff reset to 0,
+            # producing a 100% CPU spin. Raise so the reconnect/backoff path runs.
+            raise RuntimeError("WebSocket closed")
 
         while self._running and self._ws and not self._ws.closed:
             msg = await self._ws.receive()
diff --git a/tests/gateway/test_qqbot.py b/tests/gateway/test_qqbot.py
index e1f41aeccdc..816bb5f1601 100644
--- a/tests/gateway/test_qqbot.py
+++ b/tests/gateway/test_qqbot.py
@@ -2196,3 +2196,27 @@ class TestCloseCodeClassification:
         assert 4014 in fatal_codes
         assert 4001 in fatal_codes
         assert 4915 in fatal_codes
+
+
+class TestReadEventsClosedWsGuard:
+    """Regression: a closed-but-non-None ws must raise on entry, not return
+    normally, so _listen_loop goes through reconnect/backoff instead of
+    busy-looping at 100% CPU (issues #31193 / #31771)."""
+
+    def _make_adapter(self, **extra):
+        from gateway.platforms.qqbot import QQAdapter
+        return QQAdapter(_make_config(app_id="a", client_secret="b", **extra))
+
+    def test_read_events_raises_when_ws_closed_on_entry(self):
+        adapter = self._make_adapter()
+        adapter._running = True
+        adapter._ws = SimpleNamespace(closed=True)
+        with pytest.raises(RuntimeError):
+            asyncio.run(adapter._read_events())
+
+    def test_read_events_raises_when_ws_none(self):
+        adapter = self._make_adapter()
+        adapter._running = True
+        adapter._ws = None
+        with pytest.raises(RuntimeError):
+            asyncio.run(adapter._read_events())