Abstarct: Today, the lubrication industry has become an important part of the development of the machine industry and related industries. With the emergence of new issues such as optimization of consumption and conservation of non-renewable resources, as well as compliance with environmental requirements, the study of lubricants, especially in the field of nanotechnology has found a special place. Nano-engine oils are baxse oils containing added nanoparticles that can improve the tribological properties of engine oils. Diamond nanoparticles are one of the most important types of lubricant nanoparticles known in this field. The ability to understand nano-dimensional lubrication mechanisms using laboratory methods is very difficult and costly. Today, an alternative method of calculating molecular dynamics to better understand the phenomenon of lubrication and wear of nano-dimensional parts has been developed with the help of this application. The selection of the potential function as the most important simulation core has a significant effect on the wear mechanism and the forces acting on the workpiece and nanoparticles. Therefore, the validation of the molecular dynamics method has been done using the simulation of the nano indentation process. baxsed on the results of molecular dynamics simulation, the difference obtained in the nanoindentation simulation process with other studies is reported in the range of 10%. The nano wearing process of the iron workpiece is simulated in the presence of diamond nanoparticles and the effective factors are investigated. baxsed on the obtained results, the use of diamond nanoparticles makes it possible to reduce the coefficient of friction from 0.24 to 0.05. The results showed that if the surface temperature can be kept constant by cooling, increasing the sliding speed of the surfaces will reduce the coefficient of friction. Increasing the temperature and load applied to the upper block increases the coefficient of friction between the nanoparticle and the workpiece. Molecular dynamics simulation of nanowear was performed for parts with two different materials, iron and aluminum. The results showed that the coefficient of friction in two pieces of iron is less than the coefficient of friction in two pieces of different materials. The reason for this is the softness of aluminum mextal compared to iron, which causes high penetration of diamond particles into aluminum. Also in this dissertation, a preliminary study was done on the effect of the presence of post and surface prominence. baxsed on the results, it was observed that the surface that has a protrusion has the highest coefficient of friction and the surface that has a small surface cavity can have a smaller coefficient of friction. However, the presence of nanoparticles has a large difference in the coefficient of friction compared to the absence of nanoparticles.