Refractory Mo_0.5NbTiVCr_0.25 high-entropy alloy coatings were fabricated on TC4 substrates using laser cladding technology. The coatings were aged at 600, 800 and 1000 °C for 24 h and then water-cooled. The phase composition, microstructure, and mechanical properties of the high-entropy alloy coatings were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), electron backscattered diffraction (EBSD), transmission electron microscopy (TEM), Vickers hardness testing and universal friction wear testing. The results showed that high-entropy alloy coatings retained a body-centered cubic structure after different aging heat treatments. After the aging heat treatment at 800 °C, the coatings exhibited Ti-rich precipitation phases, which were verified as Ti(O,N) face-centered cubic structures by TEM technique. The optimum aging temperature was 600 °C and the hardness of the coating was HV_0.2 410. The wear mechanisms of the coatings were adhesive and abrasive wear.