Abstract: The effects of different shots and shot peening processes on surface morphology, surface plastic deformation, compressive residual stress field and fatigue life of TC4 titanium alloy after shot peening were studied. The results show that compared with the TC4 titanium alloy strengthened by cast steel shot, the surface of the alloy strengthened by ceramic shot had little fluctuation, but the working marks could be covered effectively. The surface cumulative plastic deformation on sample surface raised firstly and then saturated with the increase of shot pressure and shot time. The maximal compressive residual stress and the deepth of residual stress field could reach 610 MPa and 250 μm, respectively, either when the peening time was more than 40 s using cast steel shot or when the peening time was more than 80 s using ceramic shot with the shot pressure of 0.25 MPa. The fatigue life of TC4 titanium alloy increased by more than 10 times and 20 times, respectively, after shot peening strengthening with the two shots.