Objective To study the impact of the shot peening process on surface residual stress field of AZ91D magnesium alloy. Methods This paper established a finite element model of shot peening AZ91D magnesium alloy based on finite element platform and discussed the influence of pellet shot velocity, shot pellet diameter and incidence angle on the surface residual stress field of AZ91D magnesium alloy mainly from the aspects of the compressive residual stress layer thickness, the compressive residual stress peak and the depth of compressive residual stress peak. Besides, results of shot peening test and finite element simulation were compared. Results The compressive residual stress layer thickness and compressive residual stress peak increased significantly with the increase of shot velocity, but the increase of shot velocity had little influence on the depth of compressive residual stress. The compressive residual stress layer thickness, the compressive residual stress peak and the depth of compressive residual stress peak increased significantly with the increase of shot pellet diameter. By increasing the incidence angle, the compressive residual stress layer thickness and the compressive residual stress peak increased significantly, but the depth of the compressive residual stress peak value basically remained unchanged. The compressive residual stress layer thickness of finite element simulation was 7% smaller than the test results, the compressive residual stress of finite element simulation was 5% higher than the test results, and the depth of compressive residual stress of finite element simulation was 11% smaller than the test results. Conclusion Residual stress test results have good consistency with finite element simulation results, verifying the validity of the finite element model.