The article discusses the impact of the diversification of enterprises of the military-industrial sector on the sectoral structure of the region. On the basis of the budget approach, the specialization of the region is determined by certain types of activity - areas of the economy that may be consumers of the services of the enterprises of the military-industrial complex. The essence of this process is determined by the logical chain “diversification → specialization”. The research methods are index calculations, the hierarchy method, the pairwise comparison matrix and analytical methods. The results of the study can be applied in the development of programs of structural and industrial policy of the region.