WC-CrNi coating was deposited by HVOF technique. The sliding wear resistance of coating was investigated under self-matching frication couple and three body wear conditions, the morphology and composition change before and after wear were analyzed. The results showed that WC-CrNi coating had more homogeneous, dense microstructure owing to HVOF technique. WC-CrNi coating exhibited great differences in frictionco efficients under two wear conditions. Friction coefficient of coating was not stable, owing to the formation of three body wear increasing frictional resistance, and it experienced a severer worn. The wear mechanism of the coating under both wear conditions was different. The wear mechanism was WC layered peel under self-matching frication couple, the main abrasion model after three body wear were micro-cutting and plastic deformation.