The finite element method (FEM) and elasto-plastic self-consistent (EPSC) method were used to simulate the mechanical response of pure titanium subjected to single steel shot impacting at different shot sizes and velocities. The macroscopic and microscopic residual stresses were calculated. The results indicate that the observed macroscopic residual compressive stress increases with an increase in the shot size and impacting velocity. In addition, the macroscopic residual stress calculations correlate well with the residual elastic strain. The microscopic residual stresses lie within a range that varies with depth. Furthermore, the statistical distribution of the microscopic residual stress agrees well with the Gaussian distribution. Additionally, the dispersion of microscopic residual stresses, determined by the effective plastic deformation, is influenced by the shot size and impacting velocity. With an increase in the impacting velocity and decrease in the shot size, the standard deviation of the microscopic residual stresses at a certain depth increases.