Shot peening(SP) is one of the most effective surface strengthening treatment technologies in which compressive residual stresses are induced beneath the specimen surface. In this study, the residual stress distribution and surface roughness introduced by SP in the deformed surface layer of high manganese steel was investigated by means of three-dimensional (3D) finite element dyn mic simulation and experimental validation. The software of ABAQUS/ /Explicit was utilized in the 3D finite element dyn mic analysis of SP process, and the 3D models were set up. The effects of shot peening time, coverage rate and velocity of shot balls on the residual stress distribution and surface roughness were studied. In terms of experiments, after SP, the surface residual stresses were measured using X-ray diffraction (XRD) method. The compressive residual stresses simulated were according with the results of experiment, which verified the validity of 3D finite element dyn mic analysis. It follows from simulation that when the velocity of shot balls was constant, both the peak value and the depth of compressive residual stresses increase with the increase of velocity of shot balls, and they gradually increase with the growth of SP time before they were stable, but the depth of the peak compressive residual stresses was almost constant. Surface roughness also increase with the growth of shot peening time and velocity of shot balls.