One of the main challenges facing the industry from the past has been the phenomenon of wear. The wear is an important cause for destruction of mechanical elements and wear and tear of the parts results in loss of efficiency and reduction in the service life of devices. For this purpose, finding solutions to reduce friction coefficient and wear is of particular importance. This project has two distinct phases. In the first phase, theoretical analysis of the friction coefficient and wear rate are evaluated. In the theoretical phase, two different sub models are used to control different sizes of contact surfaces. The first sub model, which is related to modeling of contact surfaces, considers contact surface features and provides predictions about the average contact pressure and the real area of the contact. The second sub model considers the modeling of nanoparticles within the area of contact of the two surfaces. This sub model provides information about the real area of contact of the nanoparticles, the void area created around the nanoparticles, the force exerted on the nanoparticles, and the distribution of the particle deformation mechanisms. A series of experiments using pin-on-disk test setup has been conducted using different nanolubricants. The results show that the predicted wear rate and friction coefficient are in acceptable agreement with the experimentally measured values. Then, the effect of factors such as the nanoparticle volume fraction, applied load, and sliding speed on the friction coefficient and wear rate is investigated. The obtained results show that addition of nanoparticles to the base oil, results in a reduction in the friction coefficient and wear rate. There is an optimum value for the volume fraction. In the conducted experiments, it was shown that 1% volume fraction results in the most desired values. Key Words : Nanolubricant, Zinc oxide nanoparticles, Pin-on-disk test setup, Friction coefficient, Wear rate.