Nano additive CeO2 without sulfur and phosphorus was used in combination with molybdenum dithiocarbamate (MoDTC) to solve the problems of low load-bearing capacity and unsatisfactory friction-reducing property of organic molybdenum in lubricating grease. By using quartz crystal microbalance (QCM) to analyze the adsorption behavior of the composite additive, it was found that the viscoelastic co-adsorption behavior of MoDTC and CeO2 nanoparticles significantly improved the adsorption rate and equilibrium adsorption mass, which made the PB value of the composite additive increased by 77.6 % and 12.6 % compared with CeO2 and MoDTC, respectively. In the tribofilm formed by composite additive, CeO2 nanoparticles that do not undergo frictional chemical reactions with MoDTC form a flat and hard intermediate layer in the tribofilm, which improves the bearing capacity and effectively suppresses the fluctuation and accumulation of layered MoS2 on the surface. The layered structure is concentrated on the surface of the tribofilm and parallel to the friction direction, significantly reducing the sliding resistance between layers. Therefore, a thinner MoS2 layer with appropriate orientation is more conducive to improving the friction reduction performance of the grease. This results in a 33.9 % decrease in the friction coefficient of organic molybdenum, while its load-bearing capacity increases from 900 N to 1400 N, enabling lithium complex grease to achieve low friction, low wear, and high load simultaneously. Display omitted