The utility model relates to an OLT (Optical Line Terminal) device with a sealing structure, which aims to solve the technical problem that when the current OLT device is used, an unconnected plug is directly exposed outside, so that a large amount of dust is adsorbed inside a connecting jack, and the connecting jack is easily damaged, and comprises an 0LT device body, a plurality of wiring holes are formed in the rear end of the 0LT equipment body, mounting plates are mounted on the two sides of the end, close to the wiring holes, of the 0LT equipment body, a first supporting plate and a second supporting plate are arranged between the two mounting plates, and a rectangular notch is formed in the end, close to the second supporting plate, of the first supporting plate; according to the utility model, unused wiring holes can be plugged, dust can be prevented from entering the wiring holes, and connecting wires connected in the wiring holes can be limited, so that the wiring holes can be prevented from being damaged, and the service life of the wiring holes can be prolonged. Therefore, poor contact between the connector of the connecting line and the wiring hole caused by traction of the connecting line can be effectively prevented.