diff --git a/src/core/quantity-total.ts b/src/core/quantity-total.ts
new file mode 100644
index 0000000..530ef0c
--- /dev/null
+++ b/src/core/quantity-total.ts
@@ -0,0 +1,59 @@
+import type { Quantity } from './rebar/quantity';
+
+/** One line of the bridge total: a 강종 and 직경 summed over the piers. */
+export interface TotalRow {
+  grade: number;
+  size: string;
+  count: number;
+  totalM: number;
+  kg: number;
+}
+
+export interface QuantityTotal {
+  rows: TotalRow[];
+  /** Totals by 강종, in the same order as the rows. */
+  gradeKg: { grade: number; kg: number }[];
+  kg: number;
+  kgWithWaste: number;
+  ton: number;
+  couplers: { name: string; count: number }[];
+  /** Bar names with no length, left out of the totals (summed over the piers). */
+  missingCount: number;
+}
+
+/** 교량 전체 집계: sums the per-pier 재료표 by 강종 and 직경 (the per-pier values are not changed). */
+export function aggregateQuantities(items: Quantity[]): QuantityTotal {
+  const byKey = new Map<string, TotalRow>();
+  const couplers = new Map<string, number>();
+  let kg = 0;
+  let kgWithWaste = 0;
+  let missingCount = 0;
+  for (const q of items) {
+    for (const g of q.groups) {
+      for (const d of g.diameters) {
+        const key = `${g.grade}|${d.size}`;
+        const row = byKey.get(key) ?? { grade: g.grade, size: d.size, count: 0, totalM: 0, kg: 0 };
+        row.count += d.lines.reduce((n, l) => n + l.count, 0);
+        row.totalM += d.totalM;
+        row.kg += d.kg;
+        byKey.set(key, row);
+      }
+    }
+    for (const c of q.couplers) couplers.set(c.name, (couplers.get(c.name) ?? 0) + c.count);
+    kg += q.kg;
+    kgWithWaste += q.kgWithWaste;
+    missingCount += q.missing.length;
+  }
+  const rows = [...byKey.values()].sort((a, b) => a.grade - b.grade || parseInt(a.size.slice(1), 10) - parseInt(b.size.slice(1), 10));
+  const gradeKg = new Map<number, number>();
+  for (const r of rows) gradeKg.set(r.grade, (gradeKg.get(r.grade) ?? 0) + r.kg);
+  return {
+    rows,
+    gradeKg: [...gradeKg].map(([grade, value]) => ({ grade, kg: value })),
+    kg,
+    kgWithWaste,
+    ton: kgWithWaste / 1000,
+    couplers: [...couplers].map(([name, count]) => ({ name, count })),
+    missingCount,
+  };
+}
diff --git a/src/main.ts b/src/main.ts
index bd8f1ed..129177d 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -11,6 +11,7 @@ import { adjustRow, layoutText, resolveRowCounts, rowLayout, totalPiles } from '
 import { applyCopy, COPY_ITEMS, planCopy, type CopyItem } from './core/copy';
 import { copyCandidates, copyItemsFor, copyItemsWithOverrides, hasCopyItems, selectedTargets, type CopyCandidate } from './core/copy-targets';
 import { quantityTargetNames } from './core/quantity-scope';
+import { aggregateQuantities, type QuantityTotal } from './core/quantity-total';
 import { pileGeometry } from './core/geometry';
 import { rebarSummary, type RebarRow } from './core/rebar/summary';
 import { shearSegments } from './core/rebar/coping';
@@ -1814,28 +1815,49 @@ function renderQuantityScreen(): void {
   renderPierRows($<HTMLUListElement>('quantity-pier-items'), 'quantity');
   const allButton = $<HTMLButtonElement>('quantity-all');
   const generated = state.piers.filter((p) => p.model).length;
-  allButton.textContent = `전체 (${generated}기)`;
+  allButton.textContent = `전체 합계 (${generated}기)`;
   allButton.setAttribute('aria-pressed', String(state.quantityAll));
   const targets = quantityTargets();
   $('step4-status').textContent = targets.length ? (state.quantityAll ? `${targets.length}기` : targets[0].input.name) : '예정';
   $('quantity-note').textContent = targets.length
     ? `${state.quantityAll ? `전체 ${targets.length}기` : targets[0].input.name} · 할증 ${state.material.waste}% (기본 0%, 가정). 삿갓 길이는 h − 100으로 가정(Q-K5). 교각 목록에서 고른 교각만 보며, 전체를 누르면 모든 교각을 보여 줍니다.`
     : '계산된 교각이 없습니다. 교각을 생성하세요.';
-  let kg = 0;
-  let kgWithWaste = 0;
-  for (const pier of targets) {
-    if (!pier.model) continue;
-    const q = buildQuantity(rebarSummary(pier.model, state.material, state.fckByMember).rows, state.material);
-    kg += q.kg;
-    kgWithWaste += q.kgWithWaste;
+  const entries = targets.flatMap((pier) =>
+    pier.model ? [{ pier, q: buildQuantity(rebarSummary(pier.model, state.material, state.fckByMember).rows, state.material) }] : [],
+  );
+  // 전체 with more than one pier: the bridge total first (교량 전체 집계); the per-pier tables follow.
+  if (state.quantityAll && entries.length > 1) body.appendChild(bridgeTotalBlock(aggregateQuantities(entries.map((e) => e.q)), entries.length));
+  for (const { pier, q } of entries) {
     body.appendChild(el('h3', `${pier.input.name} · ${pier.input.type}`));
     if (q.missing.length) body.appendChild(el('p', `길이 미산정 ${q.missing.length}개는 합계에서 뺐습니다: ${q.missing.join(', ')}`, 'muted small'));
     body.appendChild(quantityTable(q));
     body.appendChild(el('p', `합계 ${q.kg.toFixed(1)} kg · 할증 포함 ${q.kgWithWaste.toFixed(1)} kg (${q.ton.toFixed(3)} ton) · 커플러 ${q.couplers.map((c) => `${c.name} ${c.count}개`).join(', ') || '없음'}`, 'pnote'));
   }
-  if (targets.length > 1) {
-    body.appendChild(el('p', `전체 ${targets.length}기 합계 ${kg.toFixed(1)} kg · 할증 포함 ${kgWithWaste.toFixed(1)} kg (${(kgWithWaste / 1000).toFixed(3)} ton)`, 'lbl'));
+}
+
+/** 교량 전체 집계: the 강종·직경 totals over every pier on ④ (전체). */
+function bridgeTotalBlock(total: QuantityTotal, pierCount: number): HTMLElement {
+  const wrap = el('section', undefined, 'quantity-total');
+  wrap.appendChild(el('h3', `교량 전체 집계 · ${pierCount}기`));
+  const table = el('table', undefined, 'grid-table rebar-table');
+  const head = el('thead');
+  const hr = el('tr');
+  for (const h of ['강종', '직경', '개수', '총길이 (m)', '총중량 (kg)']) hr.appendChild(el('th', h));
+  head.appendChild(hr);
+  table.appendChild(head);
+  const body = el('tbody');
+  for (const r of total.rows) {
+    body.appendChild(el('tr')).append(el('td', `SD${r.grade}`), el('td', r.size), el('td', String(r.count)), el('td', r.totalM.toFixed(1)), el('td', r.kg.toFixed(1)));
   }
+  for (const g of total.gradeKg) {
+    body.appendChild(el('tr', undefined, 'subtotal')).append(el('td', `SD${g.grade} 소계`), el('td', ''), el('td', ''), el('td', ''), el('td', g.kg.toFixed(1)));
+  }
+  table.appendChild(body);
+  wrap.appendChild(table);
+  const couplers = total.couplers.map((c) => `${c.name} ${c.count}개`).join(', ') || '없음';
+  const missing = total.missingCount ? ` · 길이 미산정 ${total.missingCount}개 제외` : '';
+  wrap.appendChild(el('p', `합계 ${total.kg.toFixed(1)} kg · 할증 포함 ${total.kgWithWaste.toFixed(1)} kg (${total.ton.toFixed(3)} ton) · 커플러 ${couplers}${missing}`, 'pnote'));
+  return wrap;
 }
 
 /** Excel: one sheet per pier and a 합계 sheet (승인 2026-10-23). */
diff --git a/src/style.css b/src/style.css
index f27de84..7212ae5 100644
--- a/src/style.css
+++ b/src/style.css
@@ -837,3 +837,4 @@ body { background: #eef1f4; font-family: 'Noto Sans KR', system-ui, sans-serif;
 .copy-panel .cp-chips .chk:has(input:checked) { border-color: #1f5fa8; background: #e3edf8; }
 .copy-panel .cp-chips .chk:has(input:disabled) { color: #8a94a3; background: #f4f6f9; }
 
+.quantity-total { margin-bottom: 16px; }
diff --git a/tests/quantity-total.test.ts b/tests/quantity-total.test.ts
new file mode 100644
index 0000000..6f412f7
--- /dev/null
+++ b/tests/quantity-total.test.ts
@@ -0,0 +1,41 @@
+import { describe, expect, it } from 'vitest';
+import { aggregateQuantities } from '../src/core/quantity-total';
+import type { Quantity } from '../src/core/rebar/quantity';
+
+/** A 재료표 with one 강종·직경 line; only the fields the aggregate reads are filled. */
+function quantity(grade: number, size: string, count: number, totalM: number, kg: number, extra: Partial<Quantity> = {}): Quantity {
+  return {
+    groups: [{ grade, kg, diameters: [{ size, dMm: 19, lines: [{ count } as never], totalM, kg }] }],
+    couplers: [],
+    missing: [],
+    kg,
+    wastePercent: 0,
+    kgWithWaste: kg,
+    ton: kg / 1000,
+    ...extra,
+  };
+}
+
+describe('aggregateQuantities (교량 전체 집계)', () => {
+  it('sums the same 강종·직경 over the piers', () => {
+    const total = aggregateQuantities([quantity(400, 'H19', 10, 100, 225), quantity(400, 'H19', 5, 50, 112.5)]);
+    expect(total.rows).toEqual([{ grade: 400, size: 'H19', count: 15, totalM: 150, kg: 337.5 }]);
+    expect(total.kg).toBe(337.5);
+  });
+
+  it('keeps different 강종 and 직경 apart and orders them by 강종 then 직경', () => {
+    const total = aggregateQuantities([quantity(500, 'S19', 4, 40, 90), quantity(400, 'H25', 2, 20, 50), quantity(400, 'H19', 1, 10, 22.5)]);
+    expect(total.rows.map((r) => `${r.grade}|${r.size}`)).toEqual(['400|H19', '400|H25', '500|S19']);
+    expect(total.gradeKg).toEqual([{ grade: 400, kg: 72.5 }, { grade: 500, kg: 90 }]);
+  });
+
+  it('adds the 할증 total and the couplers across the piers', () => {
+    const total = aggregateQuantities([
+      { ...quantity(400, 'H19', 1, 1, 100, { kgWithWaste: 110, couplers: [{ name: '커플러 H19', count: 3 }] }) },
+      { ...quantity(400, 'H19', 1, 1, 200, { kgWithWaste: 220, couplers: [{ name: '커플러 H19', count: 2 }] }) },
+    ]);
+    expect(total.kgWithWaste).toBe(330);
+    expect(total.ton).toBeCloseTo(0.33, 6);
+    expect(total.couplers).toEqual([{ name: '커플러 H19', count: 5 }]);
+  });
+});