Abstract: According to the airtight pressurization principle of fuel, environmental control, engine oxygen replenishment and other systems of a certain type of aircraft, a set of comprehensive airtight detecting device is designed. The device is composed of a platform body, an instrument panel part, a switch control panel part, an air-conditioning system, an air-tight accessory, a connecting hose and other parts. It can test the airtightness of every system of the aircraft, and is small in size and simple in operation. It can be applied to all series of the aircraft of the Air Force. Through the military test, the device can meet the requirements of airtightness testing, shorten the preparation time of aircraft maintenance, and improve the efficiency of aircraft maintenance support.