diff --git a/tensorrt_llm/serve/openai_disagg_server.py b/tensorrt_llm/serve/openai_disagg_server.py
index 67d4a418e86c..be5a65c0e45a 100644
--- a/tensorrt_llm/serve/openai_disagg_server.py
+++ b/tensorrt_llm/serve/openai_disagg_server.py
@@ -80,6 +80,12 @@ def on_resp_done(self, gen_server: str, request: UCompletionRequest, response: U
 
 
 class OpenAIDisaggServer:
+    _CONVERSATION_ID_HEADERS = (
+        "x-session-id",
+        "x-correlation-id",
+        "x-session-affinity",
+        "x-multi-turn-session-id",
+    )
 
     def __init__(self,
                  config: DisaggServerConfig,
@@ -164,15 +170,16 @@ def register_routes(self):
 
     @staticmethod
     def _extract_conversation_id(req: UCompletionRequest, raw_req: Request):
-        """Populate conversation_id from the X-Correlation-ID header.
+        """Populate conversation_id from supported session headers.
 
         When not already set in the request body, copies the header value
         into ``disaggregated_params.conversation_id``.
 
-        aiperf sends multi-turn session IDs via the ``X-Correlation-ID``
-        header (see aiperf ``base_transports.build_headers``).  We mirror
-        that convention so the ConversationRouter can provide session
-        affinity without requiring clients to set the body field.
+        Supported headers are checked in priority order: ``X-Session-ID``,
+        ``X-Correlation-ID``, ``x-session-affinity``, and
+        ``x-multi-turn-session-id``.  We mirror these conventions so the
+        ConversationRouter can provide session affinity without requiring
+        clients to set the body field.
 
         When ``disaggregated_params`` is ``None`` (standard OpenAI
         requests without disagg fields), a minimal instance is created
@@ -180,9 +187,14 @@ def _extract_conversation_id(req: UCompletionRequest, raw_req: Request):
         ``disaggregated_params`` in ``_get_ctx_request`` /
         ``_get_gen_request`` before forwarding to workers.
         """
-        header_conv_id = raw_req.headers.get("x-correlation-id")
-        if header_conv_id is None:
+        header_conv_id = None
+        for header_name in OpenAIDisaggServer._CONVERSATION_ID_HEADERS:
+            header_conv_id = raw_req.headers.get(header_name)
+            if header_conv_id is not None and header_conv_id.strip():
+                break
+        else:
             return
+
         if req.disaggregated_params is None:
             req.disaggregated_params = DisaggregatedParams(
                 request_type="context_only",
diff --git a/tests/integration/test_lists/qa/llm_function_core.txt b/tests/integration/test_lists/qa/llm_function_core.txt
index 9285526830dd..09fb9cf06f46 100644
--- a/tests/integration/test_lists/qa/llm_function_core.txt
+++ b/tests/integration/test_lists/qa/llm_function_core.txt
@@ -784,6 +784,7 @@ accuracy/test_llm_api_pytorch_multimodal.py::TestQwen3VL::test_auto_dtype[forced
 accuracy/test_llm_api_pytorch_multimodal.py::TestQwen3VL_MOE::test_auto_dtype
 accuracy/test_llm_api_pytorch_multimodal.py::TestVILA1_5_3B::test_auto_dtype
 accuracy/test_llm_api_pytorch_ray.py::TestLlama3_1_8BInstruct::test_pp2_ray
+unittest/disaggregated/test_openai_disagg_server.py
 disaggregated/test_auto_scaling.py::test_disagg_server_restart[etcd-round_robin]
 disaggregated/test_auto_scaling.py::test_disagg_server_restart[http-round_robin]
 disaggregated/test_auto_scaling.py::test_minimal_instances[etcd-round_robin]
diff --git a/tests/integration/test_lists/test-db/l0_a10.yml b/tests/integration/test_lists/test-db/l0_a10.yml
index b64d418aacfd..4839e481ef57 100644
--- a/tests/integration/test_lists/test-db/l0_a10.yml
+++ b/tests/integration/test_lists/test-db/l0_a10.yml
@@ -45,6 +45,7 @@ l0_a10:
   - unittest/others/test_tracing.py
   - unittest/disaggregated/test_disagg_openai_client.py
   - unittest/disaggregated/test_disagg_utils.py
+  - unittest/disaggregated/test_openai_disagg_server.py
   - unittest/disaggregated/test_openai_disagg_service.py
   - unittest/disaggregated/test_router.py
   - unittest/disaggregated/test_remoteDictionary.py
diff --git a/tests/unittest/disaggregated/test_openai_disagg_server.py b/tests/unittest/disaggregated/test_openai_disagg_server.py
new file mode 100644
index 000000000000..298bfcc93a3f
--- /dev/null
+++ b/tests/unittest/disaggregated/test_openai_disagg_server.py
@@ -0,0 +1,114 @@
+# Copyright (c) 2026, NVIDIA CORPORATION.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from types import SimpleNamespace
+
+from starlette.datastructures import Headers
+
+from tensorrt_llm.serve.openai_disagg_server import OpenAIDisaggServer
+from tensorrt_llm.serve.openai_protocol import CompletionRequest, DisaggregatedParams
+
+
+def _raw_request(headers: dict[str, str]):
+    return SimpleNamespace(headers=Headers(headers=headers))
+
+
+def test_extract_conversation_id_from_headers():
+    cases = [
+        ({"X-Session-ID": "session-id"}, "session-id"),
+        ({"X-Correlation-ID": "correlation-id"}, "correlation-id"),
+        ({"x-session-affinity": "session-affinity"}, "session-affinity"),
+        ({"x-multi-turn-session-id": "multi-turn-session-id"}, "multi-turn-session-id"),
+        (
+            {
+                "X-Correlation-ID": "correlation-id",
+                "X-Session-ID": "session-id",
+                "x-session-affinity": "session-affinity",
+                "x-multi-turn-session-id": "multi-turn-session-id",
+            },
+            "session-id",
+        ),
+        (
+            {
+                "x-session-affinity": "session-affinity",
+                "x-multi-turn-session-id": "multi-turn-session-id",
+            },
+            "session-affinity",
+        ),
+        (
+            {
+                "X-Session-ID": "",
+                "X-Correlation-ID": "correlation-id",
+            },
+            "correlation-id",
+        ),
+    ]
+
+    for headers, expected_conversation_id in cases:
+        request = CompletionRequest(model="test-model", prompt="hello")
+
+        OpenAIDisaggServer._extract_conversation_id(request, _raw_request(headers))
+
+        assert request.disaggregated_params is not None
+        assert request.disaggregated_params.conversation_id == expected_conversation_id
+
+
+def test_extract_conversation_id_ignores_empty_headers():
+    request = CompletionRequest(model="test-model", prompt="hello")
+
+    OpenAIDisaggServer._extract_conversation_id(
+        request,
+        _raw_request(
+            {
+                "X-Session-ID": "",
+                "X-Correlation-ID": " ",
+                "x-session-affinity": "",
+                "x-multi-turn-session-id": " ",
+            }
+        ),
+    )
+
+    assert request.disaggregated_params is None
+
+
+def test_extract_conversation_id_preserves_body_conversation_id():
+    request = CompletionRequest(
+        model="test-model",
+        prompt="hello",
+        disaggregated_params=DisaggregatedParams(
+            request_type="context_only",
+            conversation_id="body-id",
+        ),
+    )
+
+    OpenAIDisaggServer._extract_conversation_id(
+        request,
+        _raw_request({"X-Session-ID": "header-id"}),
+    )
+
+    assert request.disaggregated_params.conversation_id == "body-id"
+
+
+def test_extract_conversation_id_populates_existing_disaggregated_params():
+    request = CompletionRequest(
+        model="test-model",
+        prompt="hello",
+        disaggregated_params=DisaggregatedParams(request_type="context_only"),
+    )
+
+    OpenAIDisaggServer._extract_conversation_id(
+        request,
+        _raw_request({"x-multi-turn-session-id": "multi-turn-session-id"}),
+    )
+
+    assert request.disaggregated_params.conversation_id == "multi-turn-session-id"