From the point of view of environmental protection ,two kinds of nano-materials are chosen for this study. The preparation of nanometer materials are introduced. According to Hydrophile and Lipophile Balance (HLB), the suitable surfactants have been selected and put into lubricating oil with single nanometer particles or two kinds of nano-materials, The tribology tests were carried out in four-ball tribotester. The research results show that, the lubricating oil with nanoparticles has good properties of fri...