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S110 cast steel shot and Z300 ceramic shot were used to do the shot peening experiment, the morphology of shot peening surface was observed by scanning electron microscopy (sem) and three-dimensional contour instrument. The residual stress of shot peening surface was tested by X-ray diffraction method, the microstructure of cross section of shot peening layer was analyzed by optical microscope(OM) and electron backscattered diffraction(EBSD). The reselut shows that with the increase of shot peening intensity the roughness of shot peening surface is increased. The roughness of ceramic shot peened surface is lower than that of cast steel shot peened. Residual compressive stress on the cast steel shot peening surface is between - 860 Mpa to -1000 Mpa and with the increase of shot peening intensity of residual compressive stress is slightly reduced. Residual compressive stress on the ceramic shot peening surface is between - 1000 Mpa to -1100 Mpa and with the increase of shot peening intensity of residual compressive stress is slightly insreased. After shot peening, projectile pits are formed on GH4096 alloy surface, plastic deformation occurs, grain boundaris are curved, lattice deformation appears, cause a lot of dislocation set and low angle grain boundaries, and the grain orientation changes. The 650 ℃ high temperature fatigue life of GH4096 alloy can improve by shot peening, double shot peening promotion of fatigue life is the most obvious, ceramic shot peening strengthen effect is better than that of cast steel shot. The strengthening effect of shot peening are mutual influenced by residual stress, surface roughness and depth of strengthening layer.