diff --git a/M02_MasterTemplete/StructOptions/M02_SO_Definition.py b/M02_MasterTemplete/StructOptions/M02_SO_Definition.py
index 640d6942a..0ba02af12 100644
--- a/M02_MasterTemplete/StructOptions/M02_SO_Definition.py
+++ b/M02_MasterTemplete/StructOptions/M02_SO_Definition.py
@@ -7,7 +7,9 @@
 
 from __future__ import annotations
 
+import json
 from collections.abc import Callable
+from datetime import datetime
 from pathlib import Path
 from typing import Any
 
@@ -32,6 +34,26 @@ def history_path(version: int) -> Path:
     return Path(schema.DEFINITION_PATH).parent / HISTORY / f"판_{version}.json"
 
 
+def history() -> list[dict[str, Any]]:
+    """지난 판 목록 `[{판, 저장일}]` — 이력 `판_N.json` · 저장일 = 파일 고친 때(분까지)."""
+    folder = history_path(1).parent
+    rows = []
+    for path in folder.glob("판_*.json") if folder.is_dir() else []:
+        number = path.stem.removeprefix("판_")
+        if number.isdigit():
+            when = datetime.fromtimestamp(path.stat().st_mtime).strftime("%Y-%m-%d %H:%M")
+            rows.append({"판": int(number), "저장일": when})
+    return sorted(rows, key=lambda r: r["판"], reverse=True)
+
+
+def read_version(version: int) -> dict[str, Any]:
+    """지난 판 한 벌(읽기만) — 없으면 404."""
+    path = history_path(version)
+    if not path.is_file():
+        raise store.StoreError(404, f"판 {version} 이력이 없음")
+    return json.loads(path.read_text("utf-8"))
+
+
 def _type_errors(doc: dict[str, Any]) -> tuple[list[str], dict[str, dict[str, Any]]]:
     """(틀린 것 · 종류 → {옵션 키: 옵션}) — 종류 꼴 · 키 겹침 · 구조물군 있음."""
     errors: list[str] = []
diff --git a/M02_MasterTemplete/StructOptions/M02_SO_Router.py b/M02_MasterTemplete/StructOptions/M02_SO_Router.py
index 0dbfc8a22..b18945fdb 100644
--- a/M02_MasterTemplete/StructOptions/M02_SO_Router.py
+++ b/M02_MasterTemplete/StructOptions/M02_SO_Router.py
@@ -84,6 +84,20 @@ def get_structure_definition(session=Depends(verify_session)) -> dict:
     return _call(definition.read)
 
 
+@read_router.get("/structure-definition/history")
+def get_structure_definition_history(session=Depends(verify_session)) -> list[dict]:
+    """지난 판 목록 `[{판, 저장일}]`(새 판부터) — 로그인 누구나(PLAN 48-2)."""
+    access.require(session, "system", None)
+    return _call(definition.history)
+
+
+@read_router.get("/structure-definition/history/{version}")
+def get_structure_definition_at(version: int, session=Depends(verify_session)) -> dict:
+    """지난 판 한 벌(읽기만) — 없으면 404."""
+    access.require(session, "system", None)
+    return _call(definition.read_version, version)
+
+
 @read_router.put("/structure-definition")
 def put_structure_definition(body: DefinitionBody, session=Depends(verify_session)) -> dict:
     """정의 고쳐 씀 — 시스템 관리자만(403) · 낡은 판 409 · 검사 422 · 판 +1 · 앞 판은 이력."""
diff --git a/resources/tester/test_m02_structure_def_screen.py b/resources/tester/test_m02_structure_def_screen.py
new file mode 100644
index 000000000..c344372c5
--- /dev/null
+++ b/resources/tester/test_m02_structure_def_screen.py
@@ -0,0 +1,123 @@
+"""M02 구조물 정의 편집 화면(PLAN 48-2) — 지난 판 길 · 화면이 보내는 꼴을 서버가 받음.
+
+못박는 것
+  - 지난 판 목록 `[{판, 저장일}]` 새 판부터 · 한 벌 읽기 · 없는 판 404 · 읽기는 누구나.
+  - 화면이 고친 정의(이름 · 순서 · 안 씀 · 기준측점 · 선택지 이름 · 배치 · 그룹 형상 · 규칙)를
+    그대로 PUT 하면 판 +1 · 같은 값으로 다시 읽힘.
+  - 시스템 관리자 아니면 PUT 403(화면은 읽기만).
+  - 마스터 정본은 안 씀(사본).
+"""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+import pytest
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+from B05_Profile import B05_Profile_Structures_Schema as schema
+from common_util.common_util_auth import verify_session
+from M02_MasterTemplete.StructOptions.M02_SO_Router import read_router
+
+URL = "/api/m02/structure-definition"
+ADMIN = {"role": "SYSTEM_ADMIN", "user_id": 1}
+USER = {"role": "USER", "user_id": 2, "company_id": 1}
+
+
+@pytest.fixture
+def copy(tmp_path: Path, monkeypatch) -> Path:
+    path = tmp_path / "구조물정의.json"
+    path.write_text(Path(schema.DEFINITION_PATH).read_text("utf-8"), "utf-8")
+    monkeypatch.setattr(schema, "DEFINITION_PATH", str(path))
+    return path
+
+
+def _client(session: dict) -> TestClient:
+    app = FastAPI()
+    app.include_router(read_router)
+    app.dependency_overrides[verify_session] = lambda: session
+    return TestClient(app)
+
+
+def _screen_edit(doc: dict) -> dict:
+    """화면이 하는 고침 한 벌 — `M02_SO_Def*.ts` 가 만드는 꼴 그대로."""
+    pipe = next(t for t in doc["types"] if t["type_id"] == "pipe")
+    pipe["name"] = "배수관(고침)"
+    kind = next(o for o in pipe["options"] if o["key"] == "pipe_kind")
+    kind["label"] = "관 종류"
+    kind["choices"] = ["흄관(고침)" if c == "흄관" else c for c in kind["choices"]]
+    pipe["options"].append(
+        {
+            "key": "opt_ab12cd",
+            "label": "새 옵션 1",
+            "input": "select",
+            "choices": ["새 선택지 1", "새 선택지 2"],
+            "default": None,
+        }
+    )
+    pipe["options"][1]["enabled"] = False  # 안 씀
+    first = list(doc["구조물군"])
+    doc["구조물군"] = {k: doc["구조물군"][k] for k in [first[1], first[0], *first[2:]]}
+    doc["종류"].setdefault("pipe", {})["기준측점"] = False
+    doc["배치"]["pipe"] = {"pipe_kind": {"줄": 1, "칸": 1, "너비": 2}}
+    doc["표시"]["pipe"] = {"inlet_type": False}
+    doc["그룹"]["pipe"][1]["형상"] = {
+        "길이": {"받기": True, "뜻": "유입 보호공 연장"},
+        "높이": {"받기": False, "뜻": ""},
+    }
+    doc["규칙"] = [
+        {
+            "종류": "pipe",
+            "만약": {"옵션": "pipe_kind", "값들": ["흄관(고침)"]},
+            "그러면": {"옵션": "opt_ab12cd", "선택지": ["새 선택지 2"], "기본값": "새 선택지 2"},
+        },
+        {
+            "종류": "pipe",
+            "만약": {"옵션": "inlet_type", "값들": ["집수정"]},
+            "그러면": {"옵션": "opt_ab12cd", "보이기": False},
+        },
+    ]
+    return doc
+
+
+def test_화면_고침을_그대로_받아_판_더하기_1_지난_판_길(copy) -> None:
+    admin = _client(ADMIN)
+    doc = admin.get(URL).json()
+    assert admin.get(f"{URL}/history").json() == []
+    sent = _screen_edit(json.loads(json.dumps(doc)))
+    res = admin.put(URL, json={"판": doc["판"], "정의": sent})
+    assert res.status_code == 200, res.text
+    got = res.json()
+    assert got["판"] == doc["판"] + 1
+    for key in ("구조물군", "종류", "배치", "표시", "그룹", "규칙", "types"):
+        assert got[key] == sent[key], key
+    assert list(got["구조물군"]) == list(sent["구조물군"])  # 순서 그대로
+    rows = admin.get(f"{URL}/history").json()
+    assert [r["판"] for r in rows] == [doc["판"]] and len(rows[0]["저장일"]) == 16
+    old = admin.get(f"{URL}/history/{doc['판']}").json()
+    assert old == doc
+    assert admin.get(f"{URL}/history/999").status_code == 404
+
+
+def test_지난_판은_누구나_읽고_쓰기는_시스템_관리자만(copy) -> None:
+    user = _client(USER)
+    doc = user.get(URL).json()
+    assert user.get(f"{URL}/history").status_code == 200
+    assert user.put(URL, json={"판": doc["판"], "정의": _screen_edit(doc)}).status_code == 403
+    assert json.loads(copy.read_text("utf-8"))["판"] == doc["판"]
+
+
+def test_화면이_못_거른_틀린_규칙은_422_안_씀(copy) -> None:
+    admin = _client(ADMIN)
+    doc = admin.get(URL).json()
+    doc["규칙"] = [
+        {
+            "종류": "pipe",
+            "만약": {"옵션": "pipe_kind", "값들": ["없음"]},
+            "그러면": {"옵션": "inlet_type"},
+        }
+    ]
+    assert admin.put(URL, json={"판": doc["판"], "정의": doc}).status_code == 422
+    assert json.loads(copy.read_text("utf-8"))["판"] == doc["판"]
diff --git a/resources/tester/test_m02_structure_option_groups.py b/resources/tester/test_m02_structure_option_groups.py
index 7e3ca8312..144ac9314 100644
--- a/resources/tester/test_m02_structure_option_groups.py
+++ b/resources/tester/test_m02_structure_option_groups.py
@@ -102,8 +102,10 @@ def test_틀린_그룹은_422_낡은_판은_409(client) -> None:
     assert res.status_code == 200 and res.json()["그룹"] == {}
 
 
-def test_좌측_옵션_보이기는_시스템_관리자만() -> None:
+def test_좌측_정의_줄은_시스템_층에_늘_고쳐_씀은_시스템_관리자만() -> None:
+    """PLAN 48-2 — 다른 역할은 읽기만(화면이 칸을 잠금 · 서버 PUT 403)."""
     side = (ROOT / "M02_MasterTemplete/M02_MasterTemplete_UI_Side.ts").read_text("utf-8")
-    assert "옵션: canEdit(layer, opt.isAdmin) ? section(options.title, options.body) : null" in side
-    ui = (ROOT / "M02_MasterTemplete/StructOptions/M02_SO_Options.ts").read_text("utf-8")
-    assert "buildGroupBlock(" in ui and "buildPlaceSelect(" in ui
+    assert "옵션: section(options.title, options.body)," in side
+    folder = ROOT / "M02_MasterTemplete/StructOptions"
+    assert "buildGroupBlock(" in (folder / "M02_SO_Def.ts").read_text("utf-8")
+    assert "buildPlaceSelect(" in (folder / "M02_SO_Def_Options.ts").read_text("utf-8")
diff --git a/resources/tester/test_m02_structure_options.py b/resources/tester/test_m02_structure_options.py
index 971a94575..0bf9bd334 100644
--- a/resources/tester/test_m02_structure_options.py
+++ b/resources/tester/test_m02_structure_options.py
@@ -123,12 +123,10 @@ def test_좌측_줄은_구조물_집계_양식_아래_한_줄_같은_한_곳에
     assert "matset" not in side
     paint = side.split("function paint(): void {")[1].split("\n  }\n")[0]
     assert "if (opt.getOpen()) options.clear();" in paint  # 양식을 열면 이 줄 고름 지움
+    # 화면은 정의 한 벌로 읽고 씀(PLAN 48-2) · 보이기 체크는 정의 화면 옵션 줄
     api = (ROOT / "M02_MasterTemplete/StructOptions/M02_SO_Api.ts").read_text("utf-8")
-    assert (
-        'call("/layers/system/structure-options")' in api
-        and 'call("/structure-options", { method: "PUT"' in api
-    )
-    ui = (ROOT / "M02_MasterTemplete/StructOptions/M02_SO_Options.ts").read_text("utf-8")
+    assert 'call("/structure-definition")' in api
+    ui = (ROOT / "M02_MasterTemplete/StructOptions/M02_SO_Def_Options.ts").read_text("utf-8")
     assert 'o.phase === "detail"' in ui  # B06 전용 표시