diff --git a/B04_PreProcess/B04_PreProcess_UI_MapOverlays.ts b/B04_PreProcess/B04_PreProcess_UI_MapOverlays.ts
index 2f86f503d..c0b468e71 100644
--- a/B04_PreProcess/B04_PreProcess_UI_MapOverlays.ts
+++ b/B04_PreProcess/B04_PreProcess_UI_MapOverlays.ts
@@ -292,6 +292,8 @@ export function drawStationTicks(
     context.stroke();
 
     const label = stationLabel(chainage, interval, options.chainages ? 1 : 0) + (mc ? " (MC)" : "");
+    // MC = 사용자가 고칠 자리(507-3) — 한 단계 큰 굵은 글 · 경고색 · 바탕 = 테마 바탕(밝음 · 어두움 둘 다 읽힘)
+    context.font = mc ? "bold 13px system-ui, sans-serif" : "11px system-ui, sans-serif";
     const width = context.measureText(label).width + 6;
     const half = width / 2;
     // 겹치면 빼지 않고 **비켜 놓는다** — 직각 방향으로 반대쪽 → 한 칸 더 멀리 순서로 빈자리를
@@ -328,9 +330,9 @@ export function drawStationTicks(
       context.translate(-lx, -ly);
     }
     // 배경을 깔아 등고선 위에서도 읽히게 한다.
-    context.fillStyle = "rgba(255, 255, 255, 0.78)";
+    context.fillStyle = mc ? themeColor("--color-canvas", "#ffffff") : "rgba(255, 255, 255, 0.78)";
     context.fillRect(lx - half, ly - 8, width, 16);
-    context.fillStyle = "#222222";
+    context.fillStyle = mc ? themeColor("--color-warning", "#b8860b") : "#222222";
     context.fillText(label, lx, ly);
     context.restore();
   }
diff --git a/B05_Profile/B05_Profile_Api_Replan.ts b/B05_Profile/B05_Profile_Api_Replan.ts
index 5c773c27a..e34cec101 100644
--- a/B05_Profile/B05_Profile_Api_Replan.ts
+++ b/B05_Profile/B05_Profile_Api_Replan.ts
@@ -242,6 +242,8 @@ export interface CrossPreviewResponse {
   status: string;
   chainage_m: number;
   label: string | null;
+  /** 측점 갈래 — `curve` = MC(이름 뒤 「 (MC)」 · 507-3). */
+  kind?: string | null;
   uphill_side: string | null;
   plan_radius_m: number | null;
   curve_widening_m: number | null;
diff --git a/B05_Profile/B05_Profile_UI_RouteEdit_Cross.ts b/B05_Profile/B05_Profile_UI_RouteEdit_Cross.ts
index 07faa1632..6b637970b 100644
--- a/B05_Profile/B05_Profile_UI_RouteEdit_Cross.ts
+++ b/B05_Profile/B05_Profile_UI_RouteEdit_Cross.ts
@@ -197,7 +197,9 @@ function createPane(title: string, tag: string, empty: string): CrossPane {
       }
       // 측점은 **누가거리가 아니라 측점 표기**로 낸다(계획서 0-9 ㉑) — B05 왼쪽 아래 구조물
       // 목록이 쓰는 그 규칙이다. 서버가 주는 `STA.0+100.000` 을 그대로 쓰면 표기가 갈린다.
-      station.textContent = `${tag}${formatStation(preview.chainage_m, intervalM)}`;
+      const mc = preview.kind === "curve"; // MC = 고칠 자리(507-3) — (MC) · 크게 · 굵게 · 경고색
+      station.textContent = `${tag}${formatStation(preview.chainage_m, intervalM)}${mc ? " (MC)" : ""}`;
+      station.className = `b05-routeedit__cross-station${mc ? " b06-station--mc" : ""}`;
       draw(preview);
       foot.textContent = source ? "" : summarizeCross(preview); // 카드 = 그래프만(393-3)
     },
@@ -228,6 +230,7 @@ export function pipelineCrossAt(
     status: "success",
     chainage_m: section.chainage_m,
     label: section.label ?? null,
+    kind: section.kind ?? null,
     uphill_side: section.uphill_side ?? null,
     plan_radius_m: section.plan_radius_m ?? null,
     curve_widening_m: section.curve_widening_m ?? null,
diff --git a/B05_Profile/B05_Profile_UI_Style_RouteEdit.css b/B05_Profile/B05_Profile_UI_Style_RouteEdit.css
index 4326777db..0c674c595 100644
--- a/B05_Profile/B05_Profile_UI_Style_RouteEdit.css
+++ b/B05_Profile/B05_Profile_UI_Style_RouteEdit.css
@@ -259,6 +259,13 @@
   pointer-events: none;
 }
 
+/* MC 측점(507-3) — 한 단계 크게 · 굵게 · 경고색 */
+.b05-routeedit__cross-station.b06-station--mc {
+  font-size: var(--text-body-sm);
+  font-weight: var(--font-weight-bold);
+  color: var(--color-warning);
+}
+
 .b05-routeedit__cross-station:empty {
   display: none;
 }
diff --git a/B06_Section/B06_Section_UI_Cross_Card_Chrome.ts b/B06_Section/B06_Section_UI_Cross_Card_Chrome.ts
index 5426239be..9c3e0e531 100644
--- a/B06_Section/B06_Section_UI_Cross_Card_Chrome.ts
+++ b/B06_Section/B06_Section_UI_Cross_Card_Chrome.ts
@@ -89,6 +89,7 @@ export function appendCardHeader(
   const label = document.createElement("strong");
   label.textContent =
     stationLabel(section.chainage_m, stationInterval) + (section.kind === "curve" ? " (MC)" : "");
+  if (section.kind === "curve") label.className = "b06-station--mc"; // 507-3 크게 · 굵게 · 경고색
   const chainage = document.createElement("span");
   chainage.textContent = `${section.chainage_m.toFixed(1)}m`;
   title.append(label, chainage);
diff --git a/B06_Section/B06_Section_UI_Cross_Detail.ts b/B06_Section/B06_Section_UI_Cross_Detail.ts
index d5aee6fbc..d15697bb7 100644
--- a/B06_Section/B06_Section_UI_Cross_Detail.ts
+++ b/B06_Section/B06_Section_UI_Cross_Detail.ts
@@ -298,7 +298,10 @@ function drawChart(
 
 function titleOf(section: CrossSection): string {
   const stations = host?.detail()?.longitudinal.stations ?? [];
-  return stationLabel(section.chainage_m, inferStationInterval(stations));
+  return (
+    stationLabel(section.chainage_m, inferStationInterval(stations)) +
+    (section.kind === "curve" ? " (MC)" : "")
+  );
 }
 
 /** [상세] — 이미 열린 것은 닫고 이 측점으로 엶. */
diff --git a/B06_Section/B06_Section_UI_Longitudinal.ts b/B06_Section/B06_Section_UI_Longitudinal.ts
index d24b60047..6c5dd3dcc 100644
--- a/B06_Section/B06_Section_UI_Longitudinal.ts
+++ b/B06_Section/B06_Section_UI_Longitudinal.ts
@@ -404,7 +404,7 @@ export function createLongitudinalProfile(
   const stationTiers = labelTiers(
     data.stations.map((station, index) => ({
       x: x(station.chainage_m),
-      width: labelWidthPx(stationTexts[index], 10),
+      width: labelWidthPx(stationTexts[index], data.stations[index].kind === "curve" ? 12 : 10),
     })),
   );
   const named = data.stations.filter((station) => station.structure);
@@ -424,7 +424,8 @@ export function createLongitudinalProfile(
       x: stationX,
       y: heightPx - bottomInsetPx - 5 - LABEL_TIER_PX * tier,
       "text-anchor": "middle",
-      class: `b06-chart__station-label${tier ? " b06-chart__station-label--lifted" : ""}${tier && selected ? " b06-chart__station-label--selected" : ""}`,
+      // MC = 사용자가 고칠 자리(507-3) — 크게 · 굵게 · 경고색(_Style_Cross.css)
+      class: `b06-chart__station-label${station.kind === "curve" ? " b06-chart__station-label--mc" : ""}${tier ? " b06-chart__station-label--lifted" : ""}${tier && selected ? " b06-chart__station-label--selected" : ""}`,
     });
     if (tier) structureLabels.push(label);
     const marker = svgElement("g", {
diff --git a/B06_Section/B06_Section_UI_Style_Cross.css b/B06_Section/B06_Section_UI_Style_Cross.css
index bf1a2099b..1ac1dd830 100644
--- a/B06_Section/B06_Section_UI_Style_Cross.css
+++ b/B06_Section/B06_Section_UI_Style_Cross.css
@@ -332,6 +332,12 @@ html.is-bm-route .b06-section__notice-bar {
   font-size: var(--text-body-sm);
 }
 
+/* MC 측점 이름(507-3) — 카드 머리 글보다 한 단계 크게 · 경고색 */
+.b06-cross-card > header strong.b06-station--mc {
+  color: var(--color-warning);
+  font-size: var(--text-body);
+}
+
 /* 비정규 측점의 구조물 라벨 — kind(일반측점/BP/EP) 좌측에 자수정색 pill로 표기. */
 .b06-cross-card__structure {
   padding: 1px 6px;
@@ -395,6 +401,19 @@ html.is-bm-route .b06-section__notice-bar {
   font-size: 10px;
 }
 
+/* MC(곡선 가운데) 측점 = 사용자가 고칠 자리(507-3) — 한 단계 크게 · 굵게 · 경고색. 고름 빨강은 아래가 이김. */
+.b06-chart__station-label--mc {
+  font-size: 12px;
+  font-weight: var(--font-weight-bold);
+  fill: var(--color-warning);
+}
+
+.b06-station--mc {
+  font-size: 1.15em;
+  font-weight: var(--font-weight-bold);
+  color: var(--color-warning);
+}
+
 /* 중심고 Y축 라벨(318-2) — 눈금과 같은 10px · 둥근 상자 · 축선 앞에서 멈춤 ·
    바탕 = 불투명 섞음(겹친 눈금 글을 위에서 가림 · 319-1) · 색 = 원지반선 · 설계선(379-3 · `--b06-tag` = _Cross_Areas.css) */
 .b06-chart__center-box {
diff --git a/B06_Section/logic/B06_Section_Station_Swap.ts b/B06_Section/logic/B06_Section_Station_Swap.ts
index d17f03c52..128223999 100644
--- a/B06_Section/logic/B06_Section_Station_Swap.ts
+++ b/B06_Section/logic/B06_Section_Station_Swap.ts
@@ -292,7 +292,7 @@ export function swapCrossSections(
     const place = {
       station_id: prior && !vacated ? prior.station_id : stationIdOf(station.chainageM),
       chainage_m: station.chainageM,
-      label: formatStation(station.chainageM),
+      label: formatStation(station.chainageM) + (kind === "curve" ? " (MC)" : ""), // 서버 꼴(507-3)
       kind,
       ...(onGrid ? { grid: true } : {}),
       center_z: canon
diff --git a/B07_DesignDetail/B07_DesignDetail_Engine_Cad.py b/B07_DesignDetail/B07_DesignDetail_Engine_Cad.py
index 096427eb8..f3c623d9c 100644
--- a/B07_DesignDetail/B07_DesignDetail_Engine_Cad.py
+++ b/B07_DesignDetail/B07_DesignDetail_Engine_Cad.py
@@ -330,6 +330,11 @@ def station_no_label(chainage_m: float, interval_m: float) -> str:
     return f"No.{number}+{remainder:.1f}"
 
 
+def mc_suffix(station: dict[str, Any] | None) -> str:
+    """곡선 가운데(MC · `kind` curve) 측점 글 뒤 「 (MC)」 — 09-03 표기 위에 더함(507-3)."""
+    return " (MC)" if isinstance(station, dict) and station.get("kind") == "curve" else ""
+
+
 def _profile_alignment(longitudinal: dict[str, Any]) -> dict[str, Any]:
     alignment = longitudinal.get("profile_alignment")
     return alignment if isinstance(alignment, dict) else {}
diff --git a/B07_DesignDetail/B07_DesignDetail_Engine_Cad_Long.py b/B07_DesignDetail/B07_DesignDetail_Engine_Cad_Long.py
index e52e08bc8..1a889d09a 100644
--- a/B07_DesignDetail/B07_DesignDetail_Engine_Cad_Long.py
+++ b/B07_DesignDetail/B07_DesignDetail_Engine_Cad_Long.py
@@ -37,6 +37,7 @@ from B07_DesignDetail.B07_DesignDetail_Engine_Cad import (
     _stations,
     _text_entity,
     infer_station_interval,
+    mc_suffix,
     points_from_samples,
     polyline_entity,
     station_no_label,
@@ -155,7 +156,7 @@ def _long_table_values(
         distance = chainage - chainage_all[position - 1] if position > 0 else None
         rows.append(
             {
-                "station": station_no_label(chainage, interval_m),
+                "station": station_no_label(chainage, interval_m) + mc_suffix(station),
                 "distance": _format(distance, 1),
                 "cum_distance": _format(chainage, 1),
                 "ground": _format(ground),
diff --git a/B07_DesignDetail/B07_DesignDetail_Router_Support.py b/B07_DesignDetail/B07_DesignDetail_Router_Support.py
index 676d21211..1f61b6729 100644
--- a/B07_DesignDetail/B07_DesignDetail_Router_Support.py
+++ b/B07_DesignDetail/B07_DesignDetail_Router_Support.py
@@ -21,6 +21,7 @@ from B07_DesignDetail.B07_DesignDetail_Engine_Cad import (
     GROUND_LAYER_ID,
     build_cross_drawing,
     infer_station_interval,
+    mc_suffix,
     station_no_label,
 )
 from B07_DesignDetail.B07_DesignDetail_Engine_Cad_Basin import build_watershed_drawing
@@ -426,7 +427,8 @@ def _cross_section_input(
         ),
         "design_line": _cross_design_line(longitudinal_path, source, design),
         "quantity_table": _quantity_table(source, design),
-        "title": station_no_label(float(source.get("chainage_m", chainage)), interval),
+        "title": station_no_label(float(source.get("chainage_m", chainage)), interval)
+        + mc_suffix(source),
         "overlay": overlay,
     }
 
@@ -616,7 +618,7 @@ def _read_drawing(
     # 수량표 제목행 No. 표기: 종단 측점 간격 기준 (납품 도면 양식)
     longitudinal = _read_json(longitudinal_path)
     interval = infer_station_interval(longitudinal.get("stations") or [])
-    title = station_no_label(float(source.get("chainage_m", 0.0)), interval)
+    title = station_no_label(float(source.get("chainage_m", 0.0)), interval) + mc_suffix(source)
     # 계획고(로컬좌표 기준) + 노선 공통 범위 — 측점 이동 시 화면 배치 고정.
     design_elevation = design_elevation_from_longitudinal(
         longitudinal, float(source.get("chainage_m", 0.0))
diff --git a/B08_Quantity/B08_Quantity_Earthwork_Tables.ts b/B08_Quantity/B08_Quantity_Earthwork_Tables.ts
index efa789d0e..cb3202ffc 100644
--- a/B08_Quantity/B08_Quantity_Earthwork_Tables.ts
+++ b/B08_Quantity/B08_Quantity_Earthwork_Tables.ts
@@ -48,6 +48,8 @@ interface EarthworkRow {
   cumulative_m3: number;
   notes: string[];
   faces: Record<string, Face>;
+  /** MC(곡선 가운데) 측점 — 측점 글 뒤 「 (MC)」(507-3 · 서버 종단 `kind` curve). */
+  mc?: boolean;
 }
 
 export interface HaulRow {
@@ -184,7 +186,10 @@ function stationRow(row: EarthworkRow, first: boolean, interval: number): DataRo
   // 첫 측점은 앞이 없어 입적 · 보정량 · 면적이 없음(빈 값)
   const v = (value: number): number | null => (first ? null : value);
   const out: DataRow = {
-    station: stationLabel(row.chainage_m, interval) + (row.notes.length ? " *" : ""),
+    station:
+      stationLabel(row.chainage_m, interval) +
+      (row.mc ? " (MC)" : "") +
+      (row.notes.length ? " *" : ""),
     distance: row.distance_m,
     adjusted_total: v(row.adjusted_total_m3),
     fill_area: row.fill_area_m2,
diff --git a/B08_Quantity/B08_Quantity_Router_Earthwork.py b/B08_Quantity/B08_Quantity_Router_Earthwork.py
index 9fe57b191..8586c0b93 100644
--- a/B08_Quantity/B08_Quantity_Router_Earthwork.py
+++ b/B08_Quantity/B08_Quantity_Router_Earthwork.py
@@ -15,6 +15,8 @@
 from __future__ import annotations
 
 import asyncio
+import json
+from pathlib import Path
 from typing import Any
 from uuid import UUID
 
@@ -45,6 +47,25 @@ from config.config_db import get_db_pool
 router = APIRouter(prefix="/api/projects", tags=["B08 Earthwork"])
 
 
+def _mc_chainages(root: Path, section: dict[str, Any] | None) -> set[float]:
+    """MC(곡선 가운데 · 종단 파일 `kind` curve) 누가거리 — 토적표 측점 뒤 「 (MC)」(507-3)."""
+    relative = (section or {}).get("longitudinal_file_path")
+    path = root / str(relative) if relative else None
+    if path is None or not path.is_file():
+        return set()
+    try:
+        stations = json.loads(path.read_text(encoding="utf-8")).get("stations") or []
+    except (OSError, ValueError, AttributeError):
+        return set()
+    return {
+        round(float(station["chainage_m"]), 3)
+        for station in stations
+        if isinstance(station, dict)
+        and station.get("kind") == "curve"
+        and isinstance(station.get("chainage_m"), (int, float))
+    }
+
+
 @router.get("/{project_id}/quantity/earthwork")
 async def earthwork_table(project_id: UUID) -> dict[str, Any]:
     root = await _project_root(project_id)
@@ -61,6 +82,10 @@ async def earthwork_table(project_id: UUID) -> dict[str, Any]:
     soft = soft_rock_pct(settings)
     stations = [StationArea.from_design(row["chainage_m"], row["design"]) for row in rows]
     table = build_table(stations, mixed_conversion_factors(settings))
+    curves = await asyncio.to_thread(_mc_chainages, root, section)
+    for row in table["rows"]:
+        if round(float(row["chainage_m"]), 3) in curves:
+            row["mc"] = True
     for record in [*table["rows"], table["totals"]]:
         split_rock_columns(record, soft)
     mass_haul = ((section or {}).get("data") or {}).get("mass_haul") or {}
diff --git a/docs/raw/요구_1021/사용자요구_1021.md b/docs/raw/요구_1021/사용자요구_1021.md
index 600f75e0b..6581e8648 100644
--- a/docs/raw/요구_1021/사용자요구_1021.md
+++ b/docs/raw/요구_1021/사용자요구_1021.md
@@ -21,3 +21,12 @@
 4. b05에서 mc는 사용자가 수정해야할 부분임. 이때 mc도 붙이고 글자크기 키우고 볼트체와 색상을 변경. b07~b09에도 남길것.
 5. 검증 스크립트는 프로그램 개발에 도움을 주기 위한 스크립트는 너의 재량것 사용.
 6. 서브3 백업사본은 삭제
+
+## 요구 312 (10-21 · 사용자 · 계산 자리 창)
+
+1. 계산위치 제어 페이지사 제어안됨? 추가로로직은 45개 아님?
+2. (물음 답) 45줄 전체 표시
+
+## 요구 313 (10-21 · 사용자 · 311-2 고침)
+
+1. 노출형 횡단수로와 개거에 대해 잘 못 지시함. 다른 구조물 중 취수정이나 국가지점 번호 처럼 동작해야함. 되돌리면 될것같음. 확인
diff --git a/resources/tester/test_507_3_mc_label.py b/resources/tester/test_507_3_mc_label.py
new file mode 100644
index 000000000..da93b8ca6
--- /dev/null
+++ b/resources/tester/test_507_3_mc_label.py
@@ -0,0 +1,89 @@
+"""PLAN 507-3 — MC(곡선 가운데 · 측점 `kind` curve) 강조 · B07~B09 (MC).
+
+B05 · B06 화면 = (MC) · 한 단계 크게 · 굵게 · 경고색(`--color-warning` — 밝음 · 어두움 테마 둘 다) ·
+B07 CAD 종단 표 · 횡단 제목 = 09-03 표기 뒤 「 (MC)」(평면은 5 배수 측점만 글 · MC 글 없음) ·
+B08 토적표(B09 인쇄가 같은 표) = 서버가 MC 줄에 `mc` ·
+브라우저 측점 갈아끼움 이름 = 서버 꼴 「STA… (MC)」.
+"""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+from B07_DesignDetail.B07_DesignDetail_Engine_Cad import mc_suffix
+from B07_DesignDetail.B07_DesignDetail_Engine_Cad_Long import _long_table_values
+from B08_Quantity.B08_Quantity_Router_Earthwork import _mc_chainages
+
+ROOT = Path(__file__).resolve().parents[2]
+
+STATIONS = [
+    {"chainage_m": 580.0, "kind": "regular", "center_z": 10.0},
+    {"chainage_m": 599.0, "kind": "curve", "center_z": 10.5},
+    {"chainage_m": 600.0, "kind": "regular", "center_z": 11.0},
+]
+
+
+def _src(relative: str) -> str:
+    return (ROOT / relative).read_text(encoding="utf-8")
+
+
+def test_mc_suffix_only_curve() -> None:
+    assert mc_suffix({"kind": "curve"}) == " (MC)"
+    assert mc_suffix({"kind": "regular"}) == ""
+    assert mc_suffix({"kind": "irregular"}) == ""
+    assert mc_suffix(None) == ""
+
+
+def test_b07_long_table_station_mc() -> None:
+    rows = _long_table_values(STATIONS, STATIONS, [(0.0, 10.0), (700.0, 12.0)], {}, 20.0)
+    assert [row["station"] for row in rows] == ["No.29", "No.29+19.0 (MC)", "No.30"]
+
+
+def test_b08_mc_chainages_from_longitudinal(tmp_path: Path) -> None:
+    relative = "B06_Section/longitudinal/longitudinal.json"
+    path = tmp_path / relative
+    path.parent.mkdir(parents=True)
+    path.write_text(json.dumps({"stations": STATIONS}), encoding="utf-8")
+    assert _mc_chainages(tmp_path, {"longitudinal_file_path": relative}) == {599.0}
+    assert _mc_chainages(tmp_path, {"longitudinal_file_path": "none.json"}) == set()
+    assert _mc_chainages(tmp_path, None) == set()
+
+
+def test_b07_cross_title_mc() -> None:
+    support = _src("B07_DesignDetail/B07_DesignDetail_Router_Support.py")
+    assert support.count("+ mc_suffix(source)") == 2  # 횡단 장 제목 · 횡단 한 장 제목
+
+
+def test_b08_b09_earthwork_station_mc() -> None:
+    tables = _src("B08_Quantity/B08_Quantity_Earthwork_Tables.ts")
+    assert '(row.mc ? " (MC)" : "")' in tables
+    # B09 인쇄 토적표 = B08 표 옵션 그대로
+    assert "earthworkSheetOptions(table, interval)" in _src(
+        "B09_Estimation/draft/B09_Draft_Print_Quantity.ts"
+    )
+
+
+def test_b05_b06_screen_mc_emphasis() -> None:
+    css = _src("B06_Section/B06_Section_UI_Style_Cross.css")
+    assert "header strong.b06-station--mc {" in css  # 카드 머리 strong 규칙을 이김
+    for rule in ("\n.b06-chart__station-label--mc {", "\n.b06-station--mc {"):
+        body = css[css.index(rule) : css.index("}", css.index(rule))]
+        assert "var(--color-warning)" in body
+        assert "var(--font-weight-bold)" in body
+    # 고름 빨강이 MC 색을 이김 — 뒤에 섬
+    assert css.index(".b06-chart__station-label--mc {") < css.index(
+        ".b06-chart__station-label--selected {"
+    )
+    assert "b06-chart__station-label--mc" in _src("B06_Section/B06_Section_UI_Longitudinal.ts")
+    assert 'label.className = "b06-station--mc"' in _src(
+        "B06_Section/B06_Section_UI_Cross_Card_Chrome.ts"
+    )
+    cross = _src("B05_Profile/B05_Profile_UI_RouteEdit_Cross.ts")
+    assert "kind: section.kind ?? null" in cross
+    assert '${mc ? " b06-station--mc" : ""}' in cross
+    ticks = _src("B04_PreProcess/B04_PreProcess_UI_MapOverlays.ts")
+    assert 'mc ? "bold 13px' in ticks
+    assert 'themeColor("--color-warning"' in ticks
+    swap = _src("B06_Section/logic/B06_Section_Station_Swap.ts")
+    assert 'formatStation(station.chainageM) + (kind === "curve" ? " (MC)" : "")' in swap