The article studies the economic effect of foreign direct investment in the oil and gas sector of Azerbaijan. As a study result it was determined that it is most appropriate to direct foreign investments to the sectors capable of creating high added value. Since these investments are mainly oriented to industrial production and processing sector, there are wide export opportunities here. For the economic development of the oil and gas industry, it is advisable to increase the qualitative component of foreign direct investment. In general, the directions of foreign direct investment in the oil and gas sector correspond to the interests of the Republic of Azerbaijan, which means that it is necessary to increase the efficiency of foreign direct investment. This is possible due to optimization of strategic and operational business processes at the level of investor companies. Thus, as a result of the study, it can be said that the inflow of foreign direct investment in the oil and gas sector has had a positive impact on economic growth in the country as a whole. Keywords: oil and gas sector; foreign investment; foreign direct investment; investment environment assessment; economic development.