Depending on the special properties, rare-earth element and its compounds have been widely used in the fields of polymeric materials, inorganic non-metal materials,agriculture and chemical industry. During the past years, considerable efforts have been put on the study of its tribological application. The initial study shows that organ ophosphorid salt which contains rare earth can improve the anti-oxidation ability of grease; addition of some CeS_2 to lithium-based grease can put down the According to the special properties, rare-earth element and its compounds have been widely used in the fields of polymeric materials, inorganic non-metal materials, agriculture and chemical industry. Considerable efforts have been put on the study of its tribological application. The initial study shows that organ ophosphorid salt which contains rare earth can improve the anti-oxidation ability of grease; addition of some CeS_2 to lithium-based grease can put down the