diff --git a/litellm/proxy/_types.py b/litellm/proxy/_types.py
index c6ecb0be8b9..97f5f59d2dc 100644
--- a/litellm/proxy/_types.py
+++ b/litellm/proxy/_types.py
@@ -1930,6 +1930,13 @@ class NewTeamRequest(TeamBase):
 
     model_config = ConfigDict(protected_namespaces=())
 
+    @field_validator("team_id", mode="before")
+    @classmethod
+    def treat_blank_team_id_as_unset(cls, v: object) -> object:
+        if isinstance(v, str) and not v.strip():
+            return None
+        return v
+
 
 class GlobalEndUsersSpend(LiteLLMPydanticObjectBase):
     api_key: str | None = None
diff --git a/tests/test_litellm/proxy/management_endpoints/test_team_endpoints.py b/tests/test_litellm/proxy/management_endpoints/test_team_endpoints.py
index 30b2ab86b9a..088e82b370f 100644
--- a/tests/test_litellm/proxy/management_endpoints/test_team_endpoints.py
+++ b/tests/test_litellm/proxy/management_endpoints/test_team_endpoints.py
@@ -11083,6 +11083,14 @@ async def test_new_team_rejects_reserved_ui_session_team_id():
         mock_prisma.get_data.assert_not_called()
 
 
+@pytest.mark.parametrize("team_id", ["", "   "])
+def test_new_team_request_blank_team_id_is_unset(team_id: str) -> None:
+    from litellm.proxy._types import NewTeamRequest
+
+    assert NewTeamRequest(team_alias="t", team_id=team_id).team_id is None
+    assert NewTeamRequest(team_id="custom").team_id == "custom"
+
+
 # ---------------------------------------------------------------------------
 # PATCH /team/{team_id} — RFC 7386 JSON Merge Patch
 #