The subject of the study is the state and prospects of development of legal and economic foundations of regulation of legal relations in the sphere of national security of Ukraine. Methodology. In the process of research were used general scientific and special legal methods. Dialectical method made it possible to compare the level of legal protection of private and public interests as a type of national interests in comparison with the objects of national security. By means of analysis were determined quantitative and qualitative parameters of measures implemented within the framework of ensuring national security of Ukraine in the sphere of protected national interests of legal and economic nature. Synthesis provided the formation of common features that mediate the existence of the main categories in the sphere of national security, taking into account the time period in which the relevant measures are implemented. Comparative-legal method allowed us to identify common and distinctive features in the implementation of measures of legal and economic nature to ensure national security at different times and in the future. The purpose of the article is to establish the state and determine the prospects of development of legal and economic provision of regulation of social relations in the sphere of national security, taking into account geopolitical and internal challenges of the corresponding period of the existence of Ukrainian statehood. The results of the study showed that the state of legal and economic security of national security of Ukraine needs to be adjusted and improved taking into account the needs of the time in the geopolitical space, which is reflected in the organizational, legal and legislative work of the Verkhovna Rada of Ukraine and the research of scientists. Conclusion. The legal and economic foundations of Ukraine's national security developed under the influence of a number of factors, among which the determining ones are: international standards; creation of a legal regulation mechanism harmonizing private and public interests as part of national interests; prompt response to external and internal challenges, creation of the most effective conditions for the existence of civil society, including economic, involvement of institutions of democratic civil control in this activity. It is established that the formation of legal and economic security of national security of Ukraine took place in three stages: the initial period, when the general rules of normalization of legal relations in this area were laid down; the period of unification and systematization of normative regulations in this sphere, taking into account the proportionality of public and private national interests included in the content of national security, with the priority of the latter, in particular in the field of economic security; the period of adaptation of the regulatory framework in the field of national security to the geopolitical challenges that Ukraine faced after the Revolution of Dignity. The defining features of these stages are characterized. It is established that the legal regulation and economic provision of national security of Ukraine today is determined by the following features: in the first place among the national interests are the state sovereignty, territorial integrity, democratic constitutional order, which are associated with a real threat to these interests due to the existing aggression; a number of strategic documents in the relevant areas of national security, the content of which contains a qualification of threats, directions of state policy and appropriate response measures, in particular to ensure economic security, were categorically defined; the legal status of subjects of national security has been normalized and significantly expanded; the content of the powers and functions of these subjects is reduced, and the content of the activities of citizens and public organizations is ignored; for the first time elements of democratic civil control in the sphere of national security are introduced into the legal field. Analyzed modern scientific developments on the national security of Ukraine, which allowed to highlight promising directions of development of measures of legal and economic nature aimed at ensuring national security, including the prevention of threats in the sphere of influence of geopolitical vectors of the modern world system on the formation of Ukrainian statehood, preventing the impact of negative factors of internal and external origin, in particular: separatism; cybercrime; corruption; economic and financial threats; energy crisis; COVID-19 pandemics, etc. In addition, a characteristic feature of such measures should be their ex-ordinary effectiveness, which is mediated by the involvement of all branches of government and institutions of civil society through deep coordination of such activities, the use of international experience, cooperation with international organizations of a military-economic type, the dissemination of the jurisprudence of international courts, using the example of the European Court of Human Rights, etc.