diff --git a/docs/content/component/install.md b/docs/content/component/install.md
index 75b94ca7..0119c6c2 100644
--- a/docs/content/component/install.md
+++ b/docs/content/component/install.md
@@ -94,6 +94,22 @@ import 'clair/dist/clair.css'
 Vue.use(Clair)
 ```
 
+## 配置 zIndex 起始大小
+
+```javascript
+import Vue from 'vue'
+import Clair from 'clair'
+import 'clair/dist/clair.css'
+
+Vue.use(Clair, { zIndex: 12345 })
+```
+
+如果你是通过 `<script>` 标签直接引入 Clair 的话，则可以使用如下方式配置：
+
+```javascript
+window.Clair.setInitialZIndex(12345)
+```
+
 ## 关于 polyfill，兼谈在 vue-cli 3 项目中的使用
 
 因为 Clair 项目中使用到了一些新的 ES201x 特性（主要是 Array 和 Object 的一些拓展），在构建时我们并未对这些特性（如`Array#findIndex` `Object.assign`等）进行 polyfill。我们认为，对这些特性的 polyfill 工作应该交给开发者/使用者。
diff --git a/docs/plugins/clair.js b/docs/plugins/clair.js
index 28997468..82d37877 100644
--- a/docs/plugins/clair.js
+++ b/docs/plugins/clair.js
@@ -4,6 +4,12 @@ if (process.env.NODE_ENV === 'production') {
   require('../../src/styles/entry.css')
 }
 
-module.exports = process.env.NODE_ENV === 'production'
+const Clair = process.env.NODE_ENV === 'production'
   ? require('../../dist/clair.cjs')
   : require('../../src/entry')
+
+module.exports = {
+  install (Vue) {
+    Clair.setInitialZIndex(1999)
+  }
+}
diff --git a/src/scripts/index.js b/src/scripts/index.js
index 8f531b8c..a2dc493d 100644
--- a/src/scripts/index.js
+++ b/src/scripts/index.js
@@ -11,11 +11,15 @@ import Notification from './plugins/notification'
 import validatable from './mixins/validatable'
 import resettable from './mixins/resettable'
 
+import zIndexManager from './utils/zIndexManager'
+
 const mixins = { validatable, resettable }
 
 export const Clair = {
   mixins,
-  install (Vue) {
+  install (Vue, option = {}) {
+    zIndexManager.setInitialZIndex(option.zIndex || 1992)
+
     const VuePrototype = Vue.prototype
     const defineReadOnly = function (key, val) {
       Object.defineProperty(VuePrototype, key, {
@@ -52,5 +56,9 @@ export const Clair = {
     Vue.use(Modal)
     Vue.use(Responsive)
     Vue.use(Notification)
+  },
+
+  setInitialZIndex (zIndex) {
+    zIndexManager.setInitialZIndex(Number(zIndex) || 1992)
   }
 }
diff --git a/src/scripts/utils/zIndexManager.js b/src/scripts/utils/zIndexManager.js
index 12785bf9..c8dca953 100644
--- a/src/scripts/utils/zIndexManager.js
+++ b/src/scripts/utils/zIndexManager.js
@@ -3,5 +3,8 @@ let start = 1992
 export default {
   next () {
     return start++
+  },
+  setInitialZIndex (zIndex) {
+    start = zIndex
   }
 }