Author(s): Shaptala Natalia, Kaminska Nataliia, Kalynovskyi Bohdan, Ivanochko Iryna, Kulyk TetianaDescription: The article deals with the study of constitutionalism as a philosophical and legal category and socio-political phenomenon. Methodology: In the course of the study general and specific scientific methods were used, namely: comparative method was used when analyzing scientific categories, definitions and approaches; historical and legal method as well as logical-semantic method provided an opportunity to reveal the content of the concepts of “constitutionalism”, “constitution”; the dialectical method made it possible to consider the state of scientific researches concerning this issue’ the method of systematic analysis made it possible to identify significant features of constitutionalism; the analysis and synthesis method as well as the logical method were used to develop a holistic view on constitutionalism as philosophical and legal category; the legal modeling method was helpful in drawing conclusions of the study. The empirical basis of the research was the works of well-known domestic and foreign thinkers, specialists in the field of constitutional law. The Results of the Study: Basing on the investigations the following conclusions were made: two antagonistic constitutional models were formed in the period between the two World Wars; the issue of so-called “Muslim constitutionalism”, is worth of attention; Constitution and constitutionalism are not identical concepts; the existence of a Constitution does not solve all the problem of society; the Constitution of Orlik of 1710 and the works of Ukrainian scientists have had a significant influence on the development of constitutionalism. Practical Implications: The formation of civil society, the further development of Ukraine as a sovereign, democratic, legal and social State, its integration into European society determines the need for appropriate scientific substantiation and provision of the process of formation of national constitutional legislation, taking into account the best European and world experience of modern constitutionalism. Value/Originality: The authors’ definition of the concept of “constitutionalism” as a philosophical and legal category and socio-political phenomenon was proposed and the authors’ conclusions deriving from the research were formulated.