Abstarct: One of the main problems in the production, transmission and utilization of natural oil, sediment heavy components. One of the main heavy components in crude oil, asphaltene deposition in oil that is causing a lot of problems. The aggregation and asphaltene precipitation in the reservoir, the area around the production well, the production of oil pipelines, wellhead facilities and the crude oil lines. When the conditions governing their production takes place from an oil reservoir, the terms and conditions governing the production facility at the mouth of the well after the time changes. This condition causes the separation of oil and asphaltene deposition and the deposition of them. With so much has been said about the problems that exist for oil production, the need for extensive research on this subject is necessary. The problem of asphaltene as a major problem in many parts of oil production, has been the target of many previous studies and has a lot of information and prevention of asphaltene precipitation is obtained. But none of these methods has not fully resolved the problem of asphaltene precipitation. To fix this problem must first mechanism of aggregation and the formation of asphaltene particles known cluster and flocculation So that an appropriate solution be found to prevent this process. In a new study using population balance method to predict the distribution of clusters of asphaltene taken into consideration, but there is little information in this regard. In this thesis, the population balance model was used to study the evolution of asphaltene particle size distribution. In this model, asphaltene clots form fractal structure as well as the effects of processes of aggregation and the failure of the particles is considered. Population balance equation is initially an integral differential equation. . This equation, using discrete methods of particle size, the number of ordinary differential equations become the Runge-Kutta method for solving second-order and third in MATLAB software is used. The accuracy of the method, the comparison between the results obtained from the population balance model in this thesis with experimental results by Faraji and Soleimani Nazar (2010) was and the conclusion was that the superposition model with experimental results is good. The results of this thesis Compared with the model Faraji and Soleimani Nazar commented that the Monte Carlo method is used. The asphaltene particle size distribution is such that the first acts of fluid shear rate, the dominance of the process of gathering the average diameter of processes to increase the number of asphaltene particles. The number average diameter of asphaltene clusters to achieve the maximum, because the effect of shear rate on the fluid number average diameter is reduced And after the lapse of time because the balance of failure and clustering processes, Steady state number average diameter size of asphaltene clusters is obtained, and after this phase asphaltene deposition process begins. Also in this thesis to test the effect of two crude oil asphaltene Gadvan and Sarvak the wettability properties of glass using the contact angle measuring device is investigated. The results showed that by increasing the contact angle between the droplet of oil and asphaltene percent more glass surface and therefore surface wettability from water-wet to oil-wet state changes.