A telecommunication cabinet with anti-theft function includes a cabinet body, a cabinet door, a fan module, and a plurality of coupling parts. The cabinet body includes a cabinet and a telecommunication module. The cabinet door covers the cabinet body and is provided with a snap hole. A bottom side of the cabinet door is provided with an installation opening. The fan module includes multiple fans and an elastic clip, and the elastic clip is provided with a bump. When the fan module is placed into the cabinet door from the installation opening, the bump is positioned in the snap hole. The fan module is coupled to the bottom side of the cabinet door.