diff --git a/vllm/v1/request.py b/vllm/v1/request.py
index eefcdaf29e753..2cfcd8b63ccb2 100644
--- a/vllm/v1/request.py
+++ b/vllm/v1/request.py
@@ -58,7 +58,8 @@ def __init__(
 
         # Sanity check
         assert len(self.mm_inputs) == len(self.mm_positions)
-        assert len(self.mm_inputs) == len(self.mm_hashes)
+        if self.mm_hashes:
+            assert len(self.mm_inputs) == len(self.mm_hashes)
 
         # Cache the computed kv block hashes of the request to avoid
         # recomputing.