Abstract: A new type in situ iron based cermet composite coating was fabricated on hardened and tempered grade C steel substrate by plasma cladding.Microstructure of the coating was analyzed by SEM, XRD and EDS, respectively.Wear properties of the coating at room and high temperature were evaluated under dry sliding wear test and the wear mechanism was also discussed.Results indicated that the plasma cladding cermet composite coating consists of primary Cr₇C₃ and Cr₇C₃/γ-Fe eutectics.The coating is fine, and no big microscopic holes and cracks are found.Because of the high volume of wear-resistant reinforced phase Cr₇C₃ in the coating, wear mass loss of the coating increase extremely slowly and is not sensitive to the change of load in wear test at room temperature.Under dry sliding wear test at high temperature 400-600℃, the higher the test temperature is, the more obvious advantages the wear-resistance of the coating shows.The worn surfaces of the coating are relatively smooth and the coating possesses excellent sliding wear resistance at both room and high temperature test conditions.