To delve into the underlying lubrication mechanism of multi-component blended oils, a new blended oil system consisting of poly-alpha olefin (PAO20) and pentaerythritol polyol ester (G1866) was developed. The molecular scale compatibility of the two base oil molecules was verified using molecular dynamics, and the molecular chains were entangled and adsorbed with each other. An optimally proportioned combination of molecules was identified to solve the competitive adsorption problem and to achieve the synergistic lubrication effect. The 52.8 per cent reduction in the wear rate of blended oils can be attributed to the ester oils promoting the formation of a uniform and dense friction film at the friction interface, as well as the increased thickness and stability of the oil film.