Abstract: Rare earth elements have excellent tribological properties. In order to better understand the research trends of rare earth compounds in the field of grease, the basic information of rare earth elements and the study history of tribological properties of rare earth compounds are briefly introduced. Starting from the research of rare earth compounds in greases, the research situation of inorganic rare earth compounds and surface modified rare earth compounds as grease additives is introduced. Rare earth elements have excellent tribological properties, which can improve the friction reduction and wear resistance of lubricating grease to different degrees and are superior to ZDDP under certain conditions. The basic situation and problems in the application of inorganic rare earth compounds and polyurea-organic acid lanthanum compounds as greases thickeners are also briefly introduced. Finally, the friction reduction and anti-wear mechanism of rare earth compounds are briefly discussed, and the bright prospects for the application of rare earth compounds in the field of grease are also prospected.

Key words: rare earth, grease, friction reduction, additive, thickener