Taking into account the decline in demand for oil in the world as a result of the geopolitical situation and the consequences of the COVID-19 crisis and, as a result, the introduction of measures to limit its production, the issue of optimizing the operating costs of the oil complex is even more relevant. The purpose of this study is to develop theoretical and methodological provisions for assessing and improving the efficiency of the production activities of oil producing enterprises. The evolution of the essence and content of the concept of «efficiency» is considered, and the main modern approaches to its assessment are presented. Based on the results of the identified principles for the efficient operation of enterprises, it is proposed to evaluate the efficiency of the production activities of oil producing companies using two approaches: economic efficiency and target efficiency. The practical significance of the results of the study lies in the fact that by determining the interdependent indicators of oil fields in the Urals-Volga region on the basis of a simplex method for solving linear programming problems, a methodology has been developed for assessing the level of target efficiency of the production activity of an oil producing enterprise. The authors proposed for implementation organizational and technical measures to increase the level of efficiency of production activities by optimizing the well repair cycle of an oil producing enterprise. The obtained results of the assessment allowed the authors to identify the existing unrealized production potential under the item «Well servicing and workover» in terms of reducing the average workover time and effectively using the approved cost of a unit price. The scientific novelty of the study is determined by the developed methodology for assessing the level of target efficiency of the production activity of an oil producing enterprise. It is concluded that the developed technique can be implemented at any enterprise of the oil-producing complex.