Modern trends in the development of the theory and practice of the formation of the national interests of the state and the assessment of the state of their security show that one of the defining elements of the modern security environment for any country is the state of development of its military and economic components. The close connection of these two components of Ukraine's national security allows them to be combined into a single concept – the military-economic security of the country. Today, military-economic security can be considered as the state of protection of the national economy of the country from external and internal threats, in which it is able to meet the economic needs of a military organization for its construction, maintenance and development in order to ensure the necessary level of protection of the national interests of Ukraine as a whole. In the article, the authors present one of the possible approaches to assessing the state of the country's military-economic security in the presence of an indefinite set of input and output parameters using the method of fuzzy sets and a logical-linguistic approach. The application of this approach will make it possible to form general assessments of the state of the military-economic security of the state in order to make appropriate managerial decisions on its further development, as well as the use of fuzzy set theory during the assessment will make it possible to correlate the sensitivity and stability of the decisions made to possible changes in the input data