Abstract: The surface of Al-17Si alloy was remelted by laser.The effects of laser power and scanning speed on the microstructure and friction and wear properties of the alloy were studied.The results show that the thickness of the remelted layer increases with the increase of laser output power and decreases with the increase of scanning speed.The size of primary Si decreases obviously with the increase of laser output power and increases slightly with the increase of scanning speed.The friction and wear coefficient and wear amount decrease with the increase of laser output power and increase with the increase of scanning speed.Under the current experimental conditions, the optimal process parameters of laser surface remelting Al-17Si alloy are output power 250 W and scanning speed 600 mm/min.