diff --git a/vllm/v1/core/sched/scheduler.py b/vllm/v1/core/sched/scheduler.py
index 486ce8debc88..5bc2a16db307 100644
--- a/vllm/v1/core/sched/scheduler.py
+++ b/vllm/v1/core/sched/scheduler.py
@@ -1470,7 +1470,7 @@ def update_from_output(
                         finish_reason=request.get_finished_reason(),
                         events=request.take_events(),
                         trace_headers=request.trace_headers,
-                        num_cached_tokens=request.num_cached_tokens,
+                        num_cached_tokens=max(0, request.num_cached_tokens),
                     )
                 )