Abstract: The effects of aging at different temperatures on the microstructure and Vickers hardness of laser remelted Mo0.5NbTiVCr0.25high-entropy alloy coatings were investigated. The microstructure and microhardness of the remelted coatings and remelting heat-treated coatings were tested using X-ray diffraction(XRD), scanning electron microscopy(SEM),electron backscatter diffraction(EBSD) and Vickers hardness machine. The results show that the changes of microstructure of remelted coatings after aging heat treatment are not obvious and still dominated by dendritic structure. The size of the grains of the remelted coating increases after the aging treatment, and there is Ti-containing precipitation phase at the aging temperature of 800℃ and above. The hardness of the coatings shows an overall decreasing trend with the increase of the temperature after the aging heat treatment.