diff --git a/python/sglang/srt/managers/scheduler.py b/python/sglang/srt/managers/scheduler.py
index af16c8192..3a06f92d9 100644
--- a/python/sglang/srt/managers/scheduler.py
+++ b/python/sglang/srt/managers/scheduler.py
@@ -1545,13 +1545,13 @@ class Scheduler(
             recv_req.logprob_start_len = -1
 
         if recv_req.logprob_start_len == -1:
-            if req.is_prefill_only:
+            if recv_req.return_logprob:
+                # If return_logprob is True, return the logprobs for output tokens by default
+                req.logprob_start_len = len(req.origin_input_ids) - 1
+            elif req.is_prefill_only:
                 # For prefill-only requests with logprob_start_len == -1, set logprob_start_len
                 # beyond input sequence to skip input logprob computation entirely
                 req.logprob_start_len = len(req.origin_input_ids)
-            elif recv_req.return_logprob:
-                # If return_logprob is True, return the logprobs for output tokens by default
-                req.logprob_start_len = len(req.origin_input_ids) - 1
             else:
                 # If return_logprob is False, only the last token requires logprob computation
                 req.logprob_start_len = -1