Abstract: 45 steel surface was treated by fiber laser remelting. The effect of laser power and scanning intervals on the remelted layer was investigated, and the depth, microstructure, microhardness and wear resistance of the remelted layer were analyzed. The result indicates that the depth of remelted layer increses as the laser power increses. The microhardness distribution of the remelted layer changes periodically owing to the temper sofetning effect by the later laser. The softening effect of the later laser has been further studied by changing the scanning intervals. With appropriately increasing the scanning intervals, the remelted layer alternates between soft and harden, which improves the wear resistance and production efficiency.