Abstract: Ni55A alloy coating was prepared on the surface of 316L stainless steel by flame spraying, and then was treated by flame remelting and vacuum remelting, respectively. The effects of the remelting treatment on the micromorphology, hardness distribution and porosity of the coating were analyzed. The results show that the flame remelting and vacuum remelting could reduce the porosity of the flame sprayed coating from 4.2% to 0.34% and 0.86%, respectively, and change the bonding state from mechanical bonding to metallurgical bonding at the interface between the substrate and coating. The thickness of the diffusion layer at the interface between the coating and substrate after vacuum remelting was larger than that after flame remelting, the structure was coarser and the pore shape was more irregular. The average hardness of the coating after flame remelting and vacuum remelting increased by 60, 15 HV, respectively. The hardness of the coating after flame remelting was relatively high, and the hardness fluctuation was relatively small.