Abstarct: By passing the time and excessive use of hydrocarbon reservoirs and considering reach maturity, the rate of oilfield production has been decreased. Therefore, using multilateral wells for improvement and optimization of the reservoir performance to increase the rate of production, oilfield efficiency and reduction of the investment and operation costs has been expanded. Multilateral wells have lower pressure loss and more economical production in comparison with horizontal wells and extended reach horizontal wells. Drilling multilateral wells requires knowledge of the geological parameters (e.g. the type of reservoir, distribution permeability and porosity of reservoir), production (e.g. route wells, number of wells, type of wells) and economical (e.g. oil price and costs of drilling). Reservoir modeling is a tool which can display parameters variation and help them to be optimized. In this study, in order to optimize route drilling in multilateral wells in Jufeyr field, reservoir modeling has been used. The method was done in this way that after the data collection, 3D models of distribution of porosity, permeability and water saturation of jufeyr field was built. Then, due to the investigations, optimal boundary is selected according to the high potential reservoir. Finally, with regards to the NIOC policy for drilling multilateral wells in this field, optimal drilling route is designed.