The invention discloses a gas distribution device for spacecraft leak rate detection, including a gas turbocharger, a pressure transmitter, a filter, a pressure stabilizing chamber, a high pressure reducing valve, a medium pressure reducing valve, a driving air pressure reducing valve, a driving air stop valve, an air intake stop valve, a vacuum stop valve, a safety valve, an unloading valve, a vacuum pump, a pressure gauge and a stainless steel pipe. A gas source inlet is connected with a leak indication gas for leak rate detection. A driver inlet is connected with compressed air to drive thegas turbocharger. The leak indication gas is pressurized through the gas turbocharger, and then enters the pressure stabilizing chamber and a corresponding gas transmission loop. Two channels of highpressure and three channels of low-pressure gas are output through devices such as the pressure reducing valves, a high pressure stop value and the pressure transmitter. The vacuum pump is used for pumping out the gas in a gas transmission pipe to improve the purity of the leak indication gas. The gas distribution device of the invention meets the requirement of spacecraft service life and reliability detection, and can improve the reliability of the charging and discharging process of the leak indication gas, shorten the gas charging and discharging time and reduce the cost of leak rate detection.