diff --git a/packages/@aws-cdk/aws-appsync/lib/caching-config.ts b/packages/@aws-cdk/aws-appsync/lib/caching-config.ts
index bd189e41ee321..d02a393cc53c0 100644
--- a/packages/@aws-cdk/aws-appsync/lib/caching-config.ts
+++ b/packages/@aws-cdk/aws-appsync/lib/caching-config.ts
@@ -16,7 +16,6 @@ export interface CachingConfig {
    * The TTL in seconds for a resolver that has caching enabled.
    * Valid values are between 1 and 3600 seconds.
    *
-   * @default - No TTL
    */
-  readonly ttl?: Duration;
+  readonly ttl: Duration;
 }