The synthesis of a molybdenum disulfide (MoS2) nanocluster prepared by dialkyldithiophosphate ion modification is reported. The nanocluster was characterized by XPS, IR, UV-Vis, TEM, and elementary analysis. Results show that the MoS2 nanocluster is capped with a layer of dialkyldithiophosphate molecules. The lubrication properties of the capped nanocluster were also primarily investigated. The results show that such a nanocluster has a low kinetic friction coefficient (mu(k) < 0.1) and a good load-carrying capacity.