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The application of austenitic stainless steel is limited due to its low hardness and poor wear resistance, and improving the surface properties of stainless steel has important engineering significance to promote its application. In this work, composite coatings of MoSi₂ reinforced Co-based alloys with different mass fractions(0, 20%, 40%) were prepared using laser cladding technology. Scanning electron microscope(SEM), X-ray diffractometer(XRD), electron probe microanalyzer(EPMA) and other methods were used to study the effects of the additive amount of MoSi₂ on the microstructure, phase composition, hardness and friction and wear properties of the composite coating. Results showed that the addition of MoSi₂ changed the microstructure of the composite coating from columnar crystals to equiaxed crystals and planar dendrites, and had the effect of refining the structure. As the MoSi₂ content increased, the microhardness and wear resistance of the Co-based composite coating also increased. When the MoSi₂ content was 40%, the microhardness of the MoSi₂/Co-based composite coating was as high as 1 455 HV_0.2, and the wear rate was 6.9×10^-5 mm³/(N·m). Moreover, the hard phases(Cr₅Si₃, MoSi₂, Mo₅Si₃ and Co₂Mo₃) and the new solid solution(Fe, Cr, Co) Si₂ precipitated during solidification significantly improved the wear resistance of the composite coating. The wear mechanism of MoSi₂ reinforced Co based alloy coatings changed with the increase of MoSi₂ content, and specifically, it's transformed from the synergistic effect of abrasive wear, adhesive wear and plastic deformation into adhesive wear, brittle micro fracture and oxidative wear.