diff --git a/vllm/entrypoints/scale_out/token_in_token_out/serving.py b/vllm/entrypoints/scale_out/token_in_token_out/serving.py
index bad27aab61..bbbd85137c 100644
--- a/vllm/entrypoints/scale_out/token_in_token_out/serving.py
+++ b/vllm/entrypoints/scale_out/token_in_token_out/serving.py
@@ -203,6 +203,16 @@ class ServingTokens(GenerateBaseServing):
         # Schedule the request and get the result generator.
         result_generator: AsyncGenerator[RequestOutput, None] | None = None
 
+        # Pass disaggregated-serving parameters through to the engine.
+        if request.kv_transfer_params is not None:
+            extra = sampling_params.extra_args or {}
+            extra["kv_transfer_params"] = request.kv_transfer_params
+            sampling_params.extra_args = extra
+        if request.ec_transfer_params is not None:
+            extra = sampling_params.extra_args or {}
+            extra["ec_transfer_params"] = request.ec_transfer_params
+            sampling_params.extra_args = extra
+
         # Apply server-side ``max_tokens`` defaulting when the client did
         # not set it, matching the OpenAI-compat endpoints. ``SamplingParams``
         # defaults ``max_tokens`` to 16, which would otherwise silently cap