Ti-based composite coating is successfully fabricated on Ti811 titanium alloy surface by laser cladding. The phases, microstructures, microhardness, friction and wear resistance of the coating are studied, and the formation mechanism of TiB2-TiC composite mosaic structure is analyzed. The results show that the main phases of the coating are reinforced phases of TiC and TiB2, intermetallic compound Ti2Ni and matrix α-Ti. The misfit between the (0001) face of TiB2 and the (111) face of TiC is only 1.057%, which indicates that TiB2 can be the most effective heterogeneous nucleation core of TiC to form a TiB2-TiC composite structure. Due to dispersion strengthening, solid solution strengthening and fine-grain strengthening effect, the microhardness of the coating can reach 617 HV, which is 1.62 times that of Ti811 titanium alloy. The coating has good friction and wear resistance, its wear volume, wear depth and average friction coefficient are 175×10-3 mm3, 80.13 μm and 0.39, respectively, and the wear volume of the coating is about 26% lower than that of the substrate.