The paper is devoted to one of the most debatable issues of modern constitutional axiology, namely: the definition of the nature, essence and role of values. The author consistently reveals the significance of the category “value” in a philosophical discourse, in general axiology of law, and in the context of constitutional law. For constitutional axiology, the category of “value” appears as a multifaceted phenomenon, for which there is no common understanding today. The paper provides for differnt ways of solving this difficult task by philosophers of law and constitutionalists, i.e. to give an optimal definition of the category “a constitutional value”. Scholars determinate constitutional values through the categories of “purpose”, “priority”, “principle”, “ideal”, “idea”, “goal”, etc. On the basis of an assessment of existing approaches, the author defines her standing concerning the content of constitutional values and proposes her own definition of this basic category based on the attitude to values of the constitutional order as ideal models of the human, social and state development, acting as criterion used in the implementation and interpretation of the Constitution to achieve balanced constitutional protection of the human being, his rights and freedoms, the foundations of the constitutional order, morality, health, rights and legitimate interests of all members of the society, as well as defence of the country and security of the State.