diff --git a/python/sglang/srt/managers/schedule_batch.py b/python/sglang/srt/managers/schedule_batch.py
index ce81a8cad..cda0d4513 100755
--- a/python/sglang/srt/managers/schedule_batch.py
+++ b/python/sglang/srt/managers/schedule_batch.py
@@ -690,10 +690,12 @@ class Req(ReqDllmMixin):
     ):
         # Input and output info
         self.rid = rid
-        self.origin_input_ids_unpadded = array(
-            "q", origin_input_ids_unpadded or origin_input_ids
-        )  # Before image padding
         self.origin_input_ids = array("q", origin_input_ids)
+        self.origin_input_ids_unpadded = (
+            array("q", origin_input_ids_unpadded)
+            if origin_input_ids_unpadded
+            else self.origin_input_ids
+        )  # Before image padding
         # Each decode stage's output ids
         self.output_ids = array("q")
         # fill_ids = origin_input_ids + output_ids. Updated if chunked.