To enhance the understanding of the laser additive manufacturing process for aluminum alloy and corresponding composites, a thermal coupling finite element simulation method was employed to investigate the temperature and stress field distributions within aluminum alloy and composites during multi-pass laser cladding under varying laser process parameters. The results showed that when the laser power was 260 W, the scanning rate was 600 mm/s, and the laser energy density was 120.37 J mm^-1, the peak temperature in the molten pool could reach 1 776.93 ℃. With the increase of the laser energy density, the peak temperature gradually increased, and the width and depth of the molten pool gradually increased. Affected by the heat conduction of the adjacent laser melt pool, the temperature in the boundary area of the solidified melt pool would be raised to 1030 ℃, and a remelting occurred, while the temperature in the central area of the melt pool was raised to 300~450 ℃, and no remelting occurred. The thermal stress of SiC/AlMgScZr composite was obviously higher than that of aluminum alloy, and the high thermal cracking tendency made the composites difficult to fabricate. Proper preheating, reducing the temperature gradient and reducing the thermal stress of laser cladding could be helpful to reduce the cracking tendency of laser forming composites.