diff --git a/src/ViewerCore.tsx b/src/ViewerCore.tsx
index 17139c8..64ae271 100644
--- a/src/ViewerCore.tsx
+++ b/src/ViewerCore.tsx
@@ -48,6 +48,7 @@ export default class ViewerCore extends React.Component<ViewerProps, ViewerCoreS
     disableKeyboardSupport: false,
     noResetZoomAfterChange: false,
     noLimitInitializationSize: false,
+    defaultScale: 1,
   };
 
   private prefixCls: string;
@@ -72,8 +73,8 @@ export default class ViewerCore extends React.Component<ViewerProps, ViewerCoreS
       rotate: 0,
       imageWidth: 0,
       imageHeight: 0,
-      scaleX: 1,
-      scaleY: 1,
+      scaleX: this.props.defaultScale,
+      scaleY: this.props.defaultScale,
       loading: false,
       loadFailed: false,
     };
@@ -161,10 +162,12 @@ export default class ViewerCore extends React.Component<ViewerProps, ViewerCoreS
       width = imgSize[0];
       height = imgSize[1];
     }
+    width *= this.props.defaultScale;
+    height *= this.props.defaultScale;
     let left = (this.containerWidth - width) / 2;
     let top = (this.containerHeight - height - this.footerHeight) / 2;
-    let scaleX = 1;
-    let scaleY = 1;
+    let scaleX = this.props.defaultScale;
+    let scaleY = this.props.defaultScale;
     if (this.props.noResetZoomAfterChange) {
       scaleX = this.state.scaleX;
       scaleY = this.state.scaleY;
@@ -497,8 +500,8 @@ export default class ViewerCore extends React.Component<ViewerProps, ViewerCoreS
           transitionEnd: false,
           width: 0,
           height: 0,
-          scaleX: 1,
-          scaleY: 1,
+          scaleX: this.props.defaultScale,
+          scaleY: this.props.defaultScale,
           rotate: 1,
           imageWidth: 0,
           imageHeight: 0,
diff --git a/src/ViewerProps.ts b/src/ViewerProps.ts
index d8abd4f..901eec7 100644
--- a/src/ViewerProps.ts
+++ b/src/ViewerProps.ts
@@ -89,6 +89,9 @@ interface ViewerProps {
 
   // no limit image initialization size
   noLimitInitializationSize?: boolean;
+
+  // default scale
+  defaultScale?: number;
 }
 
 export default ViewerProps;
diff --git a/src/__tests__/viewer.test.tsx b/src/__tests__/viewer.test.tsx
index 7c961a7..13be287 100644
--- a/src/__tests__/viewer.test.tsx
+++ b/src/__tests__/viewer.test.tsx
@@ -595,4 +595,31 @@ describe('Viewer', () => {
     expect(imgNode.style.width).toBe('100px');
     expect(imgNode.style.width).toBe('100px');
   });
+
+  it('set defaultScale', () => {
+    const defaultImg = 'deafult_img';
+
+    viewerHelper.new({
+      images: [{
+        src: FAILED_IMG,
+        alt: 'lake',
+      }, {
+        src: img2,
+        alt: 'mountain',
+      }],
+      defaultImg: {
+        src: defaultImg,
+        width: 100,
+        height: 100,
+      },
+      defaultScale: .5,
+    });
+
+    viewerHelper.open();
+
+    const imgNode = $$('img.react-viewer-image')[0];
+    expect(imgNode.src).toBe(`http://localhost/${defaultImg}`);
+    expect(imgNode.style.width).toBe('50px');
+    expect(imgNode.style.width).toBe('50px');
+  });
 });