diff --git a/M01_MasterData/M01_MasterData_Router.py b/M01_MasterData/M01_MasterData_Router.py
index 3706dd065..76f24e24e 100644
--- a/M01_MasterData/M01_MasterData_Router.py
+++ b/M01_MasterData/M01_MasterData_Router.py
@@ -250,6 +250,18 @@ def get_logic_flow(key: str, file: str = "") -> dict:
     return _call(flow.get_flow, file, key)
 
 
+class FlowDraft(BaseModel):
+    file: str = ""
+    key: str = ""
+    row: dict[str, Any]
+
+
+@router.post("/logic/flow")
+def post_logic_flow(body: FlowDraft) -> dict:
+    """저장 안 한 고친 줄(옛 편집기) → 흐름 변환 — {flow, converted, notes} · 쓰기 없음."""
+    return _call(flow.get_flow, body.file, body.key, body.row)
+
+
 @router.post("/logic/new")
 def post_logic_new(body: NewLogic) -> dict:
     return _call(make.logic_new, body.logic, body.owner)
diff --git a/M01_MasterData/M01_MasterData_Store_Flow.py b/M01_MasterData/M01_MasterData_Store_Flow.py
index c2e279f44..9b5089f05 100644
--- a/M01_MasterData/M01_MasterData_Store_Flow.py
+++ b/M01_MasterData/M01_MasterData_Store_Flow.py
@@ -262,10 +262,13 @@ def _row(file: str, key: str) -> dict:
     return hit
 
 
-def get_flow(file: str, key: str) -> dict:
-    """{flow, converted, notes} — 흐름이 있으면 그대로 · 없으면 변환(파일은 안 바뀜)."""
-    row = _row(file, key)
-    if isinstance(row.get(FLOW), dict):
+def get_flow(file: str, key: str, draft: dict | None = None) -> dict:
+    """{flow, converted, notes} — 흐름이 있으면 그대로 · 없으면 변환(파일은 안 바뀜)
+    · draft = 저장 안 한 고친 줄(옛 편집기) — 늘 그 줄 그대로 변환(쓰기 없음)."""
+    row = _row(file, key) if draft is None else store._dec({**draft, "키": draft.get("키") or key})
+    if draft is not None:
+        row.pop(FLOW, None)
+    elif isinstance(row.get(FLOW), dict):
         return {"flow": {**row[FLOW], "key": key}, "converted": False, "notes": []}
     try:
         convert = importlib.import_module(CONVERT).convert
diff --git a/resources/tester/test_m01_logic_flow_save.py b/resources/tester/test_m01_logic_flow_save.py
index 312664317..dd1f29e5e 100644
--- a/resources/tester/test_m01_logic_flow_save.py
+++ b/resources/tester/test_m01_logic_flow_save.py
@@ -235,6 +235,20 @@ def test_시스템_관리자가_아니면_403(folder: Path) -> None:
     client = TestClient(app)
     before = _hashes(folder)
     assert client.get("/api/m01/logic/flow", params={"key": KEY}).status_code == 403
+    assert client.post("/api/m01/logic/flow", json={"key": KEY, "row": {}}).status_code == 403
     assert client.post("/api/m01/save", json={"files": []}).status_code == 403
     assert client.post("/api/m01/calc", json={"key": KEY, "inputs": {}}).status_code == 403
     assert _hashes(folder) == before
+
+
+def test_저장_안_한_고친_줄_변환(client: TestClient, folder: Path) -> None:
+    """POST /logic/flow — 옛 편집기 고친 줄 그대로 변환 · 파일은 안 바뀜 · 줄에 흐름이 있어도 변환."""
+    before = _hashes(folder)
+    row = copy.deepcopy(_get(client, "/api/m01/logic", key=OLD)["logic"])
+    row["이름"] = "고친 이름"
+    row["흐름"] = _flow()
+    got = _post(client, "/api/m01/logic/flow", {"key": OLD, "row": row})
+    assert got["converted"] is True and got["flow"]["key"] == OLD
+    if importlib.util.find_spec(sflow.CONVERT) is not None:
+        assert got["flow"]["name"] == "고친 이름" and got["flow"]["boxes"]
+    assert _hashes(folder) == before