diff --git a/src/alipay.ts b/src/alipay.ts
index 4b0ad42..5650456 100644
--- a/src/alipay.ts
+++ b/src/alipay.ts
@@ -453,6 +453,10 @@ export class AlipaySdk {
       authString += `,app_cert_sn=${this.config.appCertSn}`;
     }
     authString += `,nonce=${randomUUID()},timestamp=${Date.now()}`;
+    if (this.config.additionalAuthInfo) {
+      authString += `,${this.config.additionalAuthInfo}`;
+    }
+
     // 签名字符串拼接格式：
     //
     // ```txt
diff --git a/src/types.ts b/src/types.ts
index 68e2df9..708c148 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -60,4 +60,6 @@ export interface AlipaySdkConfig {
   wsServiceUrl?: string;
   /** httpClient 请求代理 */
   proxyAgent?: ProxyAgent;
+  /** Authorization 扩展信息 */
+  additionalAuthInfo?: string;
 }