A computer enclosure includes a chassis, an airflow-guiding device, and a mounting mechanism. The chassis includes a mounting bracket. The mounting bracket defines a receiving slot therein. The airflow-guiding device is mounted to the chassis adjacent to the mounting bracket. The mounting mechanism is installed on the airflow-guiding device. The mounting mechanism includes a hook received in the receiving slot and configured to mount the airflow-guiding device to the chassis. The mounting mechanism is configured to slide on the airflow-guiding device to disengage the hook from the receiving slot.