diff --git a/A00_Common/spreadsheet/spreadsheet.ts b/A00_Common/spreadsheet/spreadsheet.ts
index 341a9fc5..38951196 100644
--- a/A00_Common/spreadsheet/spreadsheet.ts
+++ b/A00_Common/spreadsheet/spreadsheet.ts
@@ -51,6 +51,8 @@ export interface SpreadsheetOptions {
   onChange?: (book: Workbook) => void;
   /** 고름이 바뀜 — 시트 id · 활성 칸 A1 · 범위 A1 */
   onSelect?: (selection: { 시트: string; 칸: string; 범위: string }) => void;
+  /** 아래 시트 탭 줄 — false 면 안 그림(산출근거 = 시트 하나) · 시트 오가기 · 새 시트 단축키 · 시트 메뉴도 끔 */
+  tabs?: boolean;
 }
 
 export interface SpreadsheetHandle {
@@ -88,7 +90,10 @@ export function createSpreadsheet(
   opts: SpreadsheetOptions = {},
 ): SpreadsheetHandle {
   const readOnly = !!opts.readOnly;
-  const root = el("div", { className: readOnly ? "ss ss--readonly" : "ss" });
+  const noTabs = opts.tabs === false;
+  const root = el("div", {
+    className: `ss${readOnly ? " ss--readonly" : ""}${noTabs ? " ss--notabs" : ""}`,
+  });
   host.append(root);
   const firstSheet = (b: Workbook) => b.시트.find((s) => s.id === b.활성) ?? b.시트[0];
   /** 시트마다 마지막 고름(탭을 오가도 그대로) */
@@ -116,14 +121,14 @@ export function createSpreadsheet(
   const ed = createEditor(ctx);
   ctx.editor = ed;
   const toolbar: PartHandle | null = readOnly ? null : mountToolbar(ctx);
-  const tabs = mountTabs(ctx);
+  const tabs: PartHandle | null = noTabs ? null : mountTabs(ctx);
   const menu: PartHandle | null = readOnly ? null : attachMenu(ctx);
   const clip = attachClipboard(ctx);
   const status = createStatusBar(ctx);
   const others = [toolbar, tabs, menu, clip, status].filter((p): p is PartHandle => !!p);
 
   grid.root.classList.add("ss-grid-host");
-  for (const node of [toolbar?.root, ed.bar, grid.root, tabs.root, status.root])
+  for (const node of [toolbar?.root, ed.bar, grid.root, tabs?.root, status.root])
     if (node) root.append(node);
   const extras = attachExtras(ctx, ed, toolbar?.root ?? null);
   others.push(...extras.parts);
diff --git a/A00_Common/spreadsheet/spreadsheet_actions.ts b/A00_Common/spreadsheet/spreadsheet_actions.ts
index 4c8fa631..9fae231f 100644
--- a/A00_Common/spreadsheet/spreadsheet_actions.ts
+++ b/A00_Common/spreadsheet/spreadsheet_actions.ts
@@ -81,6 +81,8 @@ const CTRL_SHIFT: Record<string, Act> = {
   PageUp: "prev",
 };
 
+const SHEET_ACTS = new Set<Act>(["next", "prev", "newSheet"]);
+
 /** body 에 뜬 창(.ui-confirm)이 다 닫히면 초점을 격자로 — 창을 연 바로 뒤에 부름 */
 export function watchClose(back: () => void): void {
   const w = new MutationObserver(() => {
@@ -114,8 +116,10 @@ export function mountActions(ctx: SpreadsheetContext, back: () => void): Actions
   return {
     key(e) {
       const act = pick(e);
-      if (act) go(act);
-      return !!act;
+      // 시트 탭이 없으면(산출근거) 시트 오가기 · 새 시트를 받지 않음 — 브라우저 몫으로 둠
+      if (!act || (SHEET_ACTS.has(act) && ctx.root.classList.contains("ss--notabs"))) return false;
+      go(act);
+      return true;
     },
     items: [
       item(TEXT.goTo, "goTo"),
diff --git a/A00_Common/spreadsheet/spreadsheet_data_menu.ts b/A00_Common/spreadsheet/spreadsheet_data_menu.ts
index 3339afae..307c2293 100644
--- a/A00_Common/spreadsheet/spreadsheet_data_menu.ts
+++ b/A00_Common/spreadsheet/spreadsheet_data_menu.ts
@@ -181,7 +181,14 @@ export function mountDataMenu(ctx: SpreadsheetContext, back: () => void): DataMe
             async () => (await import("./spreadsheet_names")).createNameManagerPanel,
           ),
       ],
-      [TEXT.sheets, () => void openPanel(TEXT.sheets, async () => createSheetExtraPanel)],
+      ...(ctx.root.classList.contains("ss--notabs") // 시트 탭 없음(산출근거) — 시트 창도 없음
+        ? []
+        : [
+            [
+              TEXT.sheets,
+              () => void openPanel(TEXT.sheets, async () => createSheetExtraPanel),
+            ] as MapContextMenuItem,
+          ]),
       [TEXT.grid, () => (toggleGridlines(), back())],
       ...act.items,
       {
diff --git a/M02_MasterTemplete/M02_MasterTemplete_Structure.ts b/M02_MasterTemplete/M02_MasterTemplete_Structure.ts
index 00ca7466..4e07473a 100644
--- a/M02_MasterTemplete/M02_MasterTemplete_Structure.ts
+++ b/M02_MasterTemplete/M02_MasterTemplete_Structure.ts
@@ -162,7 +162,7 @@ export function createStructurePanel(opts: StructurePanelOptions): StructurePane
     try {
       const { createSpreadsheet } = await loadSpreadsheet();
       if (mine !== seq || !basisDoc) return;
-      basis = createSpreadsheet(basisHost, basisDoc, { readOnly: true });
+      basis = createSpreadsheet(basisHost, basisDoc, { readOnly: true, tabs: false });
     } catch (error) {
       if (mine === seq) basisHost.replaceChildren(note(fill(TEXT.noSheet, why(error))));
     }
diff --git a/M02_MasterTemplete/M02_MasterTemplete_UI_Main.ts b/M02_MasterTemplete/M02_MasterTemplete_UI_Main.ts
index f59b110f..30d0576a 100644
--- a/M02_MasterTemplete/M02_MasterTemplete_UI_Main.ts
+++ b/M02_MasterTemplete/M02_MasterTemplete_UI_Main.ts
@@ -190,6 +190,7 @@ export function createMain(isAdmin: boolean, onSaved?: () => void): MainHandle {
         const { createSpreadsheet } = await import("../A00_Common/spreadsheet/spreadsheet");
         editor = createSpreadsheet(host, doc as Parameters<typeof createSpreadsheet>[1], {
           readOnly,
+          tabs: false, // 산출근거 = 시트 하나 · 탭 줄 없음
           onChange: () => (dirty = !readOnly),
         });
       } catch {