diff --git a/examples/range.js b/examples/range.js
index 2cd9a73..25c431f 100644
--- a/examples/range.js
+++ b/examples/range.js
@@ -95,7 +95,7 @@ ReactDOM.render(
     </div>
     <div style={style}>
       <p>Basic Range，`step=20` </p>
-      <Slider range step={20} defaultValue={[20, 40]} onBeforeChange={log} />
+      <Slider range step={20} defaultValue={[20, 20]} onBeforeChange={log} />
     </div>
     <div style={style}>
       <p>Basic Range，`step=20, dots` </p>
diff --git a/src/Slider.jsx b/src/Slider.jsx
index 07ea2d1..a330d7f 100644
--- a/src/Slider.jsx
+++ b/src/Slider.jsx
@@ -48,8 +48,9 @@ class Slider extends React.Component {
     if (props.range && upperBound === lowerBound) {
       if (lowerBound === max) {
         recent = 'lowerBound';
-      }
-      if (upperBound === min) {
+      } else if (upperBound === min) {
+        recent = 'upperBound';
+      } else {
         recent = 'upperBound';
       }
     } else {