To improve the economic efficiency of oil field development a new methodology for calculating the dependence of net discounted cash flow on the length of the horizontal wellbore, which is based on technical solutions developed at the department of development and operation of oil and gas fields, and the use of software products simulation of field development process is proposed. Based on the results of the studies performed, technical and economic proposals were made for the development of the Cherepanovskoye elevation of the Mishkinskoye field.