diff --git a/src/datetime-picker/TimePicker.js b/src/datetime-picker/TimePicker.js
index 7f021a6cd..4f6326e82 100644
--- a/src/datetime-picker/TimePicker.js
+++ b/src/datetime-picker/TimePicker.js
@@ -144,14 +144,14 @@ export default createComponent({
       const hour = hourColumn.values[hourIndex] || hourColumn.values[0];
       const minute = minuteColumn.values[minuteIndex] || minuteColumn.values[0];
 
-      let innerValue = this.formatValue(`${hour}:${minute}`);
+      let innerValue = `${hour}:${minute}`;
 
       if (this.unit === 'second') {
         const second = secondColumn.values[secondIndex] || secondColumn.values[0];
         innerValue += `:${second}`
       }
 
-      this.innerValue = innerValue;
+      this.innerValue = this.formatValue(innerValue);
       this.updateColumnValue();
     },
 
diff --git a/src/datetime-picker/demo/index.vue b/src/datetime-picker/demo/index.vue
index 23736f9c2..d9ea3e38b 100644
--- a/src/datetime-picker/demo/index.vue
+++ b/src/datetime-picker/demo/index.vue
@@ -99,16 +99,20 @@
       </demo-block>
 
       <demo-block card :title="t('datetimeType')">
+          <div>value: {{value.datetime}}</div>
           <van-datetime-picker :value.sync="value.datetime" type="datetime" :title="t('datetimeType')" />
       </demo-block>
       <demo-block card :title="t('datetimeType')">
+          <div>value: {{value.datetime}}</div>
           <van-datetime-picker :value.sync="value.datetime" type="datetime" unit="minute" :title="t('datetimeType')" />
       </demo-block>
 
       <demo-block card :title="t('timeType')">
+          <div>value: {{value.time}}</div>
           <van-datetime-picker :value.sync="value.time" type="time" :title="t('timeType')" />
       </demo-block>
       <demo-block card :title="t('timeType')">
+          <div>value: {{value.secondTime}}</div>
           <van-datetime-picker :value.sync="value.secondTime" type="time" unit="second" :title="t('timeType')" />
       </demo-block>
   </demo-section>
diff --git a/yarn.lock b/yarn.lock
index 4ce8b1905..8d9bec538 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -6045,6 +6045,11 @@ decamelize@^1.1.0, decamelize@^1.1.2, decamelize@^1.2.0:
   resolved "https://registry.npmjs.org/decamelize/-/decamelize-1.2.0.tgz"
   integrity "sha1-9lNNFRSCabIDUue+4m9QH5oZEpA=sha512-z2S+W9X73hAUUki+N+9Za2lBlun89zigOyGrsax+KUQ6wKW4ZoWpEYBkGhQjwAjjDCkWxhY0VKEhk8wzY7F5cA== sha512-z2S+W9X73hAUUki+N+9Za2lBlun89zigOyGrsax+KUQ6wKW4ZoWpEYBkGhQjwAjjDCkWxhY0VKEhk8wzY7F5cA=="
 
+decimal.js@^10.4.3:
+  version "10.4.3"
+  resolved "https://registry.yarnpkg.com/decimal.js/-/decimal.js-10.4.3.tgz#1044092884d245d1b7f65725fa4ad4c6f781cc23"
+  integrity sha512-VBBaLc1MgL5XpzgIP7ny5Z6Nx3UrRkIViUkPUdtl9aya5amy3De1gsUUSB1g3+3sExYNjCAsAznmukyxCb1GRA==
+
 decode-uri-component@^0.2.0:
   version "0.2.0"
   resolved "https://registry.npmjs.org/decode-uri-component/-/decode-uri-component-0.2.0.tgz"