In order to improve the defects of low hardness and poor wear resistance of titanium alloy (TC4) parts, B4C/Cobalt-based alloy composite coating was prepared on TC4 surface by laser cladding technology. The temperature field of the composite coating was numerically simulated by finite element method, and the influence of laser power on the single laser cladding of B4C/Cobalt-based composite coating was studied by the combination of surface morphologies and micro-hardness. The results show that the peak temperature and depth of molten pool increases with the increase of laser power, whereas the width of molten pool almost has no change. When the laser power is 1 600 W, the micro-hardness of the composite coating reaches the highest value of 618.7 HV(2 N loading force), which is 79.2% higher than that of TC4 substrate, and the strengthening mechanism of B4C is revealed.