In order to study the influence of shot type on fatigue performance in shot peening, a single detail structure fatigue test piece with a stress concentration coefficient of 1.5 was designed. Ceramic shot and cast steel shot of different sizes were used for shot peening of 7055-T7451 aluminum alloy test pieces at low, medium, and high strength, and fatigue performance testing was conducted. The test data was processed and analyzed using the detail fatigue rating （DFR） method to obtain the gain in fatigue performance of the test piece after shot peening. The results show that shot peening can significantly improve the fatigue life of materials, which can increase by 9%~57%. The type of shot used for shot peening has a significant impact on the fatigue gain of the test piece. Under the same strength, the effect of ceramic shot peening is better than that of cast steel shot. When the types of shot are the same, the effect of small size shot peening is better than that of large size shot peening; The effect of ceramic shot peening strength on fatigue performance exhibits a parabolic shape, which means that the fatigue performance first increases and then decreases with the increase of shot peening strength.