diff --git a/vllm/v1/engine/utils.py b/vllm/v1/engine/utils.py
index 7b0f00d14c..1f0b9bbb19 100644
--- a/vllm/v1/engine/utils.py
+++ b/vllm/v1/engine/utils.py
@@ -403,6 +403,11 @@ class CoreEngineActorManager:
             range(dp_size), local_dp_ranks, placement_groups
         ):
             dp_vllm_config = copy.deepcopy(vllm_config)
+            if dp_size > 1:
+                # Append the DP rank to instance_id so that per-engine
+                # identifiers (e.g. Ray actor names in RayExecutorV2) are
+                # unique across DP replicas.
+                dp_vllm_config.instance_id = f"{dp_vllm_config.instance_id}_dp{index}"
             dp_vllm_config.parallel_config.placement_group = pg
             local_client = index < local_engine_count