Abstract: In order to investigate the laser damage effects on the metal surface, a two-dimension numercial model for the laser ablation of metal was established based on the heat conduction theory and the equivalent temperature of phase transformation. The processes of the laser ablation of aluminum target with nanosecond laser pulse were simulated by using finite element analysis method. The ablation shape and temperature field distribution of aluminum target irradiated by laser were obtained. The results show that when the energy of laser pulse is given, the ablation radius becomes smaller and the ablation depth becomes deeper with the longer pulse width. The bigger spot size,the more ablation is near the spot size. Ablation radius decreases because of the low power density after the spot size increases to some value.