Abstract: The NiCrBSi+Ni/MoS₂ composite coatings are prepared on the TC4 substrate by laser cladding technique. The surface morphology and the elemental composition of the composite coatings in the vacuum and after atomic oxygen irradiation are investigated. The friction and wear properties in two kinds of environments are determined by using the vacuum friction and wear tester. It is shown that after the atomic oxygen irradiation, some elements and compounds in the NiCrBSi+Ni/MoS₂ composite coatings are decomposed and oxidized, but exhibit no distinct change of the material properties or lubricant coating damage are found. Compared with TC4, the composite coating exhibits good lubrication and friction reduction in both kinds of environments. The results show that the NiCrBSi+Ni/MoS₂ composite coating has adequate ability to resist the atomic oxygen irradiation.