This system can carry out helium leak detection for metal oxide arresters and similar products. The detection method is reliable and effective, and the structure is novel. technical parameter 　　1) Leak detection beat: 5 pieces/minute; 　　2) The minimum detectable leak rate: ≦1x10-8Pa·m3/s; 　　3) With automatic air mixing function; 　　4) With the functions of air inflation outside the box, leak detection inside the box, and fixed-point leak detection;