This gear shot peening machine, configures Mitsubishi PLC & touch screen, is design with 4 indexing and 4 workstations, and its recovery system consisting of bucket elevator and blower. Two sets of blast gun are applied in this machine, the first set is use for peening internal gear teeth, and the other set is for external gear teeth. As per the peening requirement, operator can select to peening the external & internal gear teeth separately, or select the preset peening process on the touch screen to peen them alternately.