In the conditions of transformational changes in Ukraine, the issue of national security is one of the key ones. Military intervention in relation to our state, crisis processes in the economy, politics, finance, social sphere, opposition to political extremism, separatism, collaborationism, various forms and methods of crime in today's realities are acute, painful problems that require an immediate solution. The state is the defining institution of the political system of Ukraine, the main guarantor of the constitutional system and performs the functions of ensuring national security through legislative, executive and judicial authorities, the key place among which should belong to the parliament, which provides regulatory and legal support for national security in the state. The Verkhovna Rada of Ukraine, within the functional powers defined by the Constitution of Ukraine, determines the principles of internal and foreign policy, the foundations of national security, forms the legislative framework in this area, approves decisions on the introduction of a state of emergency and martial law, mobilization, determination of the general structure, number, and functions of allies and participation in military-political alliances; professionalism of the personnel of the armed forces; the size of military expenditures, the state of military science and the nature of military doctrine. These factors are important objects of Ukraine's military policy. Because it is the effective functioning of the security and defense sector and defense in conditions of limited state resources and the consistent and constructive support of Ukraine by the international community that is the key to the successful provision of socio-political and socio-economic development and regional security, the restoration of peace in Ukraine. Without proper legislative support, the national security system of Ukraine will be formal and unable to protect the rights and freedoms of the Ukrainian people. The article uses a number of general scientific, legal, and philosophical methods and approaches. The worldview position of the authors is determined by the development of the modern complex state of our country, martial law, challenges, globalist military intervention of Russia, etc. All this requires characteristic approaches and methodological expansion of the problem on the basis of the civilizational approach, conceptual approaches of jurisprudence with the application of systemic methods. The theoretical and practical significance of the study includes a comprehensive analysis of the outlined issues of institutional support of the problem of national security in Ukraine at the legislative level.