Based on the gridless SPH numerical technique of Ls-dyna hydrocode, the characteristics of debris clouds originating from impact of spherical projectile on the plate at different velocities were simulated. At the same time the different physical courses due to various impact angles were obtained. The simulation results show a good agreement with those from the experiments presented in the literature concerned. The generation and expansion of debris clouds were clearly simulated. It indicates that the SPH algorithm can make the qualitative description for phenomena of hypervelocity impact, thus proving the feasibility of the numerical simulation of hypervelocity impact on the basis of the SPH algorithm.