Abstract: Phenolic composite coatings (PF) filled with cerium oxide particles (CeO₂), and CeO₂ coupled molybdenum disulfide (MoS₂) were prepared by spray coating method, respectively. The effects of micro sized CeO₂ particles and molybdenum disulfide on the tribological properties of PF coatings under boundary lubrication conditions were investigated. The results indicated that the addition of merely 1% CeO₂ leaded to significant reductions in both the friction coefficient and wear rate of the PF coating, achieving decreases of 67.22% and 83.97%, respectively. When 1% CeO₂ was incorporated into a 7% MoS₂-filled PF composite coating, the friction coefficient and wear rate were reduced to as low as 0.012 and 6×10⁻⁷ mm³/(N·m), respectively, highlighting a pronounced synergistic effect between CeO₂ and MoS₂ in enhancing friction reduction and anti-wear properties. The analyses of micro/nano structure and composition of the transfer film revealed that the CeO₂ and MoS₂ particles released during the friction process promoting the formation of uniform transfer film. Moreover, the transferred debris and frictional chemical products were mixed and compacted, improving the load-bearing capacity and solid lubrication characteristics of the transfer film, effectively compensating for the insufficient oil film during boundary lubrication. Therefore, this work provided significant guidance for the design of phenolic coatings using on the surface of moving parts under boundary lubrication conditions.