The process of the oil field operation at the late stage is characterized by a significant content of mechanical impurities in the extracted raw materials and a high rate of water encroachment. Water encroachment plays a significant role in the processes of formation sand carry-over and the destruction of incompetent rocks of productive horizons in deposits. Today, to intensify the drainage of formation fluid from production wells, it is necessary to increase the depth of descent and to use more productive pumps. However, this leads to the growth of the draw down pressure and, as a rule, to more intensive sloughing of mechanical impurities out of the reservoir. First of all, the sand taken out of the formation is a highly abrasive agent, which causes the wear not only of the pump elements, but also of the tubings, valves, throttles, etc. Predicting the impact of mechanical impurities on the elements of the pumping equipment for oil production is a complex task that requires consideration of many different factors. The sand which is carried out of wells is accumulated in the pipelines. Besides, it is accumulated in measuring units, separators, valves and other parts of group metering and pumping units. Process tanks and reservoirs at oil or condensate treatment plants are clogged with sand. To combat sloughing of sand, in most cases the method of filtration is used. This method is not the most effective, but it is reliable, low cost, and environmentally friendly. Several constructions of downhole filters are analyzed. To evaluate the efficiency of the downhole filter, its research is carried out using simulation modeling. The dependence of the number of sloughed particles on their diameter is established in accordance with the hydrodynamic processes and characteristics of the working environment