Accommodating cavity gas leakage testing method and device

The invention discloses an accommodating cavity gas leakage testing method and device. The method comprises the steps: 1, measuring the volume V of a containing cavity, the sealing the containing cavity, and after the air pressure of air in the containing cavity is kept stable, measuring the absolute pressure value P1 and the absolute temperature value T1 of the air in the containing cavity; 2, after S seconds, measuring an absolute pressure value P2 and an absolute temperature value T2 of the gas in the accommodating cavity; 3, calculating the leakage rate MXL of the containing cavity, judging whether the leakage rate MXL of the containing cavity is larger than the maximum allowable leakage value or not, if yes, the containing cavity does not meet the sealing requirement, and if not, thecontaining cavity meets the sealing requirement. The specific value of leakage can be determined, the test precision is accurately controlled, and whether the leakage index of the containing cavity meets the requirement or no