diff --git a/plugins/openclaw-weixin/src/api/api.ts b/plugins/openclaw-weixin/src/api/api.ts
index 8e2a6c7..27b4764 100644
--- a/plugins/openclaw-weixin/src/api/api.ts
+++ b/plugins/openclaw-weixin/src/api/api.ts
@@ -65,11 +65,10 @@ function randomWechatUin(): string {
   return Buffer.from(String(uint32), "utf-8").toString("base64");
 }
 
-function buildHeaders(opts: { token?: string; body: string }): Record<string, string> {
+function buildHeaders(opts: { token?: string }): Record<string, string> {
   const headers: Record<string, string> = {
     "Content-Type": "application/json",
     AuthorizationType: "ilink_bot_token",
-    "Content-Length": String(Buffer.byteLength(opts.body, "utf-8")),
     "X-WECHAT-UIN": randomWechatUin(),
   };
   if (opts.token?.trim()) {
@@ -99,7 +98,7 @@ async function apiFetch(params: {
 }): Promise<string> {
   const base = ensureTrailingSlash(params.baseUrl);
   const url = new URL(params.endpoint, base);
-  const hdrs = buildHeaders({ token: params.token, body: params.body });
+  const hdrs = buildHeaders({ token: params.token });
   logger.debug(`POST ${redactUrl(url.toString())} body=${redactBody(params.body)}`);
 
   const controller = new AbortController();