diff --git a/tauri-app/src/hooks/useCoverFabric.ts b/tauri-app/src/hooks/useCoverFabric.ts
index dc9fd06..c0916f2 100644
--- a/tauri-app/src/hooks/useCoverFabric.ts
+++ b/tauri-app/src/hooks/useCoverFabric.ts
@@ -284,14 +284,10 @@ export function useCoverFabric() {
       await loadCustomFont().catch(() => {
       });
 
-      // 调整 canvas 内部渲染尺寸以匹配目标分辨率
-      if (canvas.width !== targetWidth || canvas.height !== targetHeight) {
-        canvas.setDimensions(
-          { width: targetWidth, height: targetHeight },
-          { cssOnly: false }
-        );
-      }
-
+      // Canvas 内部渲染尺寸始终保持 1080×1920 不变，
+      // 通过 resolutionScale 缩放所有元素，避免 Fabric.js 尺寸突变导致文字错乱。
+      // CSS 显示尺寸由 initCanvas 固定为 337×600，不受此处影响。
+      void targetHeight; // 保留接口兼容性，实际通过 multiplier 在导出时处理高度
       const resolutionScale = targetWidth / CANVAS_WIDTH;
 
       canvas.clear();
@@ -392,11 +388,12 @@ export function useCoverFabric() {
     [loadBackground, loadAvatarImage]
   );
 
-  // 导出 PNG
-  const exportPng = useCallback((): string => {
+  // 导出 PNG（通过 multiplier 缩放到目标分辨率）
+  const exportPng = useCallback((targetWidth?: number): string => {
     const canvas = fabricCanvasRef.current;
     if (!canvas) {return '';}
-    return canvas.toDataURL({ format: 'png', quality: 1, multiplier: 1 });
+    const multiplier = (targetWidth ?? CANVAS_WIDTH) / CANVAS_WIDTH;
+    return canvas.toDataURL({ format: 'png', quality: 1, multiplier });
   }, []);
 
   // 销毁
diff --git a/tauri-app/src/pages/VideoCreation/CoverDesign.tsx b/tauri-app/src/pages/VideoCreation/CoverDesign.tsx
index 9a18a76..18017b9 100644
--- a/tauri-app/src/pages/VideoCreation/CoverDesign.tsx
+++ b/tauri-app/src/pages/VideoCreation/CoverDesign.tsx
@@ -332,7 +332,7 @@ export default function CoverDesign() {
         }
       }
 
-      const dataUrl = exportPng();
+      const dataUrl = exportPng(videoResolution?.width);
       if (!dataUrl) {
         throw new Error('封面设计失败');
       }