The modified reduced graphene oxide (MRGO) was uniformly dispersed in PAO6 base oil by ultrasonic ball milling and microwave ball milling. The dispersion stability of additives in oil and the tribological properties of lubricating oil were tested, and the mechanism of anti-friction and anti-wear was discussed. The results show that the tribological properties of base oil are improved with the introduction of MRGO. Moreover, compared with adding MRGO directly to the base oil, the coupling effect of ultrasonic ball milling and microwave ball milling can bring into full play the tribological performance of additives, because ultrasonic and microwave ball milling can achieve stable dispersion of additives in base oil, thus improving the tribological properties of lubricating oil.