The powder metallurgymolybdenum-rich steels, used in a new friction system, were prepared. Effect of carbide types onwear-resisting property of the steels was studied. The wear behavior of the steels and the couple part were also studied. M2C carbides and M6C carbides exit in the steels. The friction pair materials enter steady working condition within 50 seconds and have good match capability. On dry frication test, crisp M2C carbides, which are distributed along crystal border, dissever the matrix and decrease wearresisting property of the steels obviously. Gobbet carbides consist of many fine grainy M6C carbides. This kind of carbide has high bond strength with the matrix and is useful to good wear-resisting property of the steels.