diff --git a/docs/specs/2018-04-03-zh-cn.md b/docs/specs/2018-04-03-zh-cn.md
index dd0982e1e..2de458609 100644
--- a/docs/specs/2018-04-03-zh-cn.md
+++ b/docs/specs/2018-04-03-zh-cn.md
@@ -64,6 +64,7 @@ Resources:
 
 - [Aliyun::Serverless::Service](#aliyunserverlessservice)
   - [Aliyun::Serverless::Function](#aliyunserverlessfunction)
+- [Aliyun::Serverless::CustomDomain](#aliyunserverlesscustomdomain)
 - [Aliyun::Serverless::Api](#aliyunserverlessapi)
 - [Aliyun:Serverless::TableStore](#aliyunserverlesstablestore)
   - [Aliyun:Serverless::TableStore::Table](#aliyunserverlesstablestoretable)
@@ -122,6 +123,33 @@ MyService: # service name
         Timeout: 15
 ```
 
+#### Aliyun::Serverless::CustomDomain
+
+创建自定义域名。自定义域名是函数计算的一个功能，可以通过自定义域名调用函数执行。
+
+##### 属性
+属性名称 | 类型 | 描述
+---|:---:|---
+Protocol | `string` | 自定义域名支持的协议类型。
+RouteConfig | [PathConfig](#pathConfig) 数组 | 路由表，配置路径和函数的映射关系。
+
+##### 示例：Aliyun::Serverless::CustomDomain
+
+```yaml
+abc.com: # domain name
+     Type: 'Aliyun::Serverless::CustomDomain'
+     Properties:
+       Protocol: HTTP
+       RouteConfig:
+         routes: 
+           '/a':
+             serviceName: serviceA
+             functionName: functionA
+           '/b':
+             serviceName: serviceB
+             functionName: functionB
+```
+
 #### Aliyun::Serverless::Api
 
 创建可通过 HTTPS 端点调用的阿里云 API 网关资源和方法的集合。
@@ -491,3 +519,16 @@ CodeUri 用来指定代码存储的位置，它可以用来指定：
 oss 文件：`CodeUri: 'oss://my-fc-testt/2018/helloworld.zip'`。
 
 其中，当指定为 oss 文件时，形式为 `CodeUri: 'oss://bucket-name/filepath'`。
+
+<a name="pathConfig"></a>
+#### PathConfig
+
+PathConfig 用于设置自定义域名中路径与函数的映射关系。
+
+示例：
+
+```
+  '/a': # path
+        serviceName: serviceA
+        functionName: functionA
+```
\ No newline at end of file
diff --git a/docs/specs/2018-04-03.md b/docs/specs/2018-04-03.md
index 7564783e2..721675a88 100644
--- a/docs/specs/2018-04-03.md
+++ b/docs/specs/2018-04-03.md
@@ -61,7 +61,9 @@ Resources:
 All property names in Aliyun Fun are **case sensitive**.
 
 ### Resource types
-
+- [Aliyun::Serverless::Service](#aliyunserverlessservice)
+  - [Aliyun::Serverless::Function](#aliyunserverlessfunction)
+- [Aliyun::Serverless::CustomDomain](#aliyunserverlesscustomdomain)
 - [Aliyun::Serverless::Api](#aliyunserverlessapi)
 - [Aliyun::Serverless::TableStore](#aliyunserverlesstablestore)
   - [Aliyun:Serverless::TableStore::Table](#aliyunserverlesstablestoretable)
@@ -117,6 +119,33 @@ MyService: # service name
         Timeout: 15
 ```
 
+#### Aliyun::Serverless::CustomDomain
+
+create Custom Domain。Custom Domain is a feature of Function Compute, users can invoke functions via Custom Domain.
+
+##### Properties
+Property Name | Type | Description
+---|:---:|---
+Protocol | `string` | supported protocol
+RouteConfig | [PathConfig](#pathConfig) array | mappings of paths and functions
+
+##### Example：Aliyun::Serverless::CustomDomain
+
+```yaml
+abc.com: # domain name
+     Type: 'Aliyun::Serverless::CustomDomain'
+     Properties:
+       Protocol: HTTP
+       RouteConfig:
+         routes: 
+           '/a':
+             serviceName: serviceA
+             functionName: functionA
+           '/b':
+             serviceName: serviceB
+             functionName: functionB
+```
+
 #### Aliyun::Serverless::Api
 
 Creates a collection of Aliyun API Gateway resources and methods that can be invoked through HTTPS endpoints.
@@ -387,4 +416,15 @@ oss file: `CodeUri: 'oss://my-fc-testt/2018/helloworld.zip'`。
 
 Among them, when specified as an oss file, the format is `CodeUri: 'oss://bucket-name/filepath'`.
 
+<a name="pathConfig"></a>
+#### PathConfig
+
+PathConfig is used to set mapping relation of path and function.
 
+Example：
+
+```
+  '/a': # path
+        serviceName: serviceA
+        functionName: functionA
+```