The feasibility of reduced-friction coating against U-Nb alloy made by plasma spray technique was investigated. Sn soft coating, Sn/ ZrO2 dual coating, Sn and ZrO2 mixing coating and ZrO2 hard coating were prepared by plasma spray technique. The sliding friction behavior of these coatings against U-Nb alloy was evaluated. The friction characteristic of Sn coating is similar to Sn/ ZrO2 dual coating and its friction coefficient is the lowest among the four coatings. Friction coefficient of ZrO2 coating, into which Sn was added, is decreased little, while friction coefficient of ZrO2 hard coating is stabilized at high value with the increase of sliding number of cycles. ZrO2 coating by plasma spray technique plays no role in reducing friction against U-Nb alloy. Plough is the main friction mechanism of these coatings.