Abstract: The environments of a space station during its launch and mission may cause a space station structure leak to put the astronaut in danger and make the equipments fail to work. The idea of monitoring leak of space station with direction vacuum gauge is put forward in the paper, which consists of three circles in the connections of testing cabin and service cabin, below testing cabin and joint, below service cabin and joint, fixed relative to the space station, for the direction vacuum gauges to move by step electromotors and scan the space station’s outside cabin. The sensitivity and location precision of monitoring leak by direction vacuum gauge are analyzed.