diff --git a/packages/web/src/components/InteractiveGraphVisualization.tsx b/packages/web/src/components/InteractiveGraphVisualization.tsx
index 040a7cbc..70bfe946 100644
--- a/packages/web/src/components/InteractiveGraphVisualization.tsx
+++ b/packages/web/src/components/InteractiveGraphVisualization.tsx
@@ -3888,8 +3888,21 @@ export function InteractiveGraphVisualization({ onResetLayout }: InteractiveGrap
       const t = d3.zoomIdentity.translate(w / 2 - graphX * k, h / 2 - graphY * k).scale(k);
       svg.transition().duration(350).call(zoomBehaviorRef.current.transform as any, t);
     };
+    // Mini-map wheel/pinch → zoom the main view to a target scale, centered on
+    // the gesture's graph point. Clamped to the same scaleExtent as the main
+    // zoom; applied via the shared zoom behavior so state + handlers stay in sync.
+    (window as any).miniMapZoom = (graphX: number, graphY: number, targetK: number) => {
+      if (!svgRef.current || !containerRef.current || !zoomBehaviorRef.current) return;
+      const svg = d3.select(svgRef.current);
+      const k = Math.max(0.1, Math.min(4, targetK));
+      const w = containerRef.current.clientWidth;
+      const h = containerRef.current.clientHeight;
+      const t = d3.zoomIdentity.translate(w / 2 - graphX * k, h / 2 - graphY * k).scale(k);
+      svg.transition().duration(120).call(zoomBehaviorRef.current.transform as any, t);
+    };
     return () => {
       delete (window as any).miniMapNavigate;
+      delete (window as any).miniMapZoom;
     };
   }, []);
 
diff --git a/packages/web/src/components/MiniMap.tsx b/packages/web/src/components/MiniMap.tsx
index bd78d0cf..9307efd4 100644
--- a/packages/web/src/components/MiniMap.tsx
+++ b/packages/web/src/components/MiniMap.tsx
@@ -25,6 +25,61 @@ export function MiniMap({ width = 192, height = 128 }: { width?: number; height?
   const [nodes, setNodes] = useState<Record<string, MiniMapNode>>({});
   const [viewport, setViewport] = useState<Viewport | null>(null);
   const nodeTypesRef = useRef<Record<string, string>>({});
+  // Live minimap-px <-> graph-coord conversion params, updated each render so
+  // the native (non-passive) wheel/touch listeners can map a gesture point to
+  // a graph point and drive the main view's zoom.
+  const geomRef = useRef({ minX: 0, minY: 0, offsetX: 0, offsetY: 0, scale: 1, k: 1 });
+  const svgElRef = useRef<SVGSVGElement>(null);
+
+  // Wheel + pinch on the minimap zoom the MAIN view (centered on the gesture
+  // point). Attached natively with passive:false so we can preventDefault and
+  // stop the page from scrolling while zooming the map.
+  useEffect(() => {
+    const el = svgElRef.current;
+    if (!el) return undefined;
+    const toGraph = (clientX: number, clientY: number) => {
+      const r = el.getBoundingClientRect();
+      const g = geomRef.current;
+      return {
+        x: g.minX + (clientX - r.left - g.offsetX) / g.scale,
+        y: g.minY + (clientY - r.top - g.offsetY) / g.scale,
+      };
+    };
+    const onWheel = (e: WheelEvent) => {
+      e.preventDefault();
+      const p = toGraph(e.clientX, e.clientY);
+      const factor = e.deltaY < 0 ? 1.18 : 1 / 1.18;
+      (window as any).miniMapZoom?.(p.x, p.y, geomRef.current.k * factor);
+    };
+    let pinchDist0 = 0;
+    let pinchK0 = 1;
+    const dist = (t: TouchList) => Math.hypot(t[0].clientX - t[1].clientX, t[0].clientY - t[1].clientY);
+    const mid = (t: TouchList) => ({ x: (t[0].clientX + t[1].clientX) / 2, y: (t[0].clientY + t[1].clientY) / 2 });
+    const onTouchStart = (e: TouchEvent) => {
+      if (e.touches.length === 2) { pinchDist0 = dist(e.touches); pinchK0 = geomRef.current.k; }
+    };
+    const onTouchMove = (e: TouchEvent) => {
+      if (e.touches.length === 2 && pinchDist0 > 0) {
+        e.preventDefault();
+        const m = mid(e.touches);
+        const p = toGraph(m.x, m.y);
+        (window as any).miniMapZoom?.(p.x, p.y, pinchK0 * (dist(e.touches) / pinchDist0));
+      }
+    };
+    const onTouchEnd = () => { pinchDist0 = 0; };
+    el.addEventListener('wheel', onWheel, { passive: false });
+    el.addEventListener('touchstart', onTouchStart, { passive: false });
+    el.addEventListener('touchmove', onTouchMove, { passive: false });
+    el.addEventListener('touchend', onTouchEnd);
+    return () => {
+      el.removeEventListener('wheel', onWheel);
+      el.removeEventListener('touchstart', onTouchStart);
+      el.removeEventListener('touchmove', onTouchMove);
+      el.removeEventListener('touchend', onTouchEnd);
+    };
+    // Re-run when the svg appears: the minimap renders a "No nodes yet" div
+    // first (svg ref null), then the <svg> once positions arrive — attach then.
+  }, [Object.keys(nodes).length > 0]);
 
   useEffect(() => {
     (window as any).updateMiniMapPositions = (positions: Record<string, { x: number; y: number; type?: string }>) => {
@@ -75,6 +130,7 @@ export function MiniMap({ width = 192, height = 128 }: { width?: number; height?
   const scale = Math.min(width / spanX, height / spanY);
   const offsetX = (width - spanX * scale) / 2;
   const offsetY = (height - spanY * scale) / 2;
+  geomRef.current = { minX, minY, offsetX, offsetY, scale, k: viewport?.k || 1 };
 
   const toMini = useCallback(
     (gx: number, gy: number) => ({
@@ -117,6 +173,7 @@ export function MiniMap({ width = 192, height = 128 }: { width?: number; height?
 
   return (
     <svg
+      ref={svgElRef}
       width="100%"
       height="100%"
       viewBox={`0 0 ${width} ${height}`}
diff --git a/tests/diagnostics/minimap-zoom.spec.ts b/tests/diagnostics/minimap-zoom.spec.ts
new file mode 100644
index 00000000..518984a7
--- /dev/null
+++ b/tests/diagnostics/minimap-zoom.spec.ts
@@ -0,0 +1,58 @@
+import { test, expect, Page } from '@playwright/test';
+import { login, TEST_USERS } from '../helpers/auth';
+
+/**
+ * Minimap wheel/pinch zoom: a wheel over the minimap zooms the MAIN view
+ * (centered on the gesture point). Asserts the main view's zoom scale changes.
+ */
+const GRAPH_ID = 'subgraph-power-shared';
+
+async function mainScale(page: Page): Promise<number> {
+  return page.evaluate(() => {
+    const g = document.querySelector('.graph-container svg .main-graph-group') as SVGGElement | null;
+    const t = g?.getAttribute('transform') || '';
+    const m = /scale\(([-0-9.]+)/.exec(t);
+    return m ? parseFloat(m[1]) : 1;
+  });
+}
+
+test.describe('minimap zoom diagnostic @geometry', () => {
+  test.describe.configure({ timeout: 120_000 });
+
+  test('wheel on the minimap changes the main view zoom', async ({ page }) => {
+    await page.setViewportSize({ width: 1440, height: 900 });
+    await login(page, TEST_USERS.ADMIN);
+    await page.waitForTimeout(1500);
+    await page.evaluate((gid) => {
+      localStorage.setItem('currentGraphId', gid);
+      localStorage.setItem('graphdone.quality.override', 'HIGH');
+    }, GRAPH_ID);
+    await page.reload();
+    await page.waitForTimeout(6000);
+
+    const mini = page.locator('[data-testid="mini-map"]');
+    await mini.waitFor({ timeout: 15000 });
+    const box = await mini.boundingBox();
+    expect(box, 'minimap is visible').not.toBeNull();
+
+    const cx = box!.x + box!.width / 2;
+    const cy = box!.y + box!.height / 2;
+    await page.mouse.move(cx, cy);
+    const before = await mainScale(page);
+
+    // Zoom IN: real (trusted) wheel events at the minimap centre.
+    for (let i = 0; i < 3; i++) { await page.mouse.wheel(0, -120); await page.waitForTimeout(250); }
+    await page.waitForTimeout(400);
+    const afterIn = await mainScale(page);
+
+    // Zoom OUT.
+    for (let i = 0; i < 4; i++) { await page.mouse.wheel(0, 120); await page.waitForTimeout(250); }
+    await page.waitForTimeout(400);
+    const afterOut = await mainScale(page);
+
+    // eslint-disable-next-line no-console
+    console.log(`[minimap-zoom] before=${before} afterIn=${afterIn} afterOut=${afterOut}`);
+    expect(afterIn, 'wheel-in increases main zoom').toBeGreaterThan(before);
+    expect(afterOut, 'wheel-out decreases zoom below the zoomed-in level').toBeLessThan(afterIn);
+  });
+});