The effect of a variety of factors on the laser heating from the theory and numerical simulation, by using 1 064 nm Nd:YAG long pulse laser interaction with metal. The phenomenon and problem in the process of the laser-matter interaction are analyzed and simulated, as for laser-metal interaction research at home and abroad, especially the temperature field and stress field of the long pulse laser-metal interaction are analyzed theoretically. The effect of the basic mechanism of the laser reflection, the absorption and the transformation on the target material, the temperature field, the stress field and the melting temperature of the metal material heated by the laser, the moving velocity of the solid-liquid interface, the liquid mass transfer, the material gasification and the ablation mass transfer are analyzed.