diff --git a/packages/core/src/oidc/init.ts b/packages/core/src/oidc/init.ts
index 9c616fa0c..067f94f9e 100644
--- a/packages/core/src/oidc/init.ts
+++ b/packages/core/src/oidc/init.ts
@@ -57,6 +57,7 @@ export default async function initOidc(app: Koa): Promise<Provider> {
           const scope = scopes.map(({ name }) => name).join(' ');
 
           return {
+            accessTokenFormat: 'jwt',
             scope,
             accessTokenTTL,
           };