Object: the process of formation and development of frontier theory. Objective: analyzing of the evolution of the concept of frontier, structure and functions of comparative frontiers as direction in modern historiography and also clarify of expediency limit the usefulness of frontier theory in the history of Ukraine. Methods: comparative and historical, retrospective, problem-chronological, ethnographic, sociological, gender, cultural and anthropological. Results: for the first time analyzed creative heritage of F. Turner in Ukrainian historiography, found regional differences in the interpretation of the concept of frontier by historians of the United States, Latin America, Canada, Australia, Russia, Ukraine, proposed own periodizations of the development of the Australian frontier and the frontier concept application in medievalism, found that the etymology of the term frontier and the presence of its counterparts not only in the languages of the West, and East indicates that the phenomenon of frontier and attempts of its interpretation - much older than the word and scientific concept, grounded translating the concept of frontier by Ukrainian, analyzed heritage of founder of the theory of migration I. Bowman, interpreted ideas of O. Lattimor, analyzed career of V. McNeill and his concept for interpretation of the of history of Eurasian as the steppe frontier of Europe, explored the legacy of the "school of Spanish borderlands" of G. Bolton, analyzed the historiography of ancient Rome in the light of the theory of sinusitis, found that in Russian historiography unison for frontier concept are the emphasizes of Soloviev and Kliuchevskii on factor of colonization as a key factor in the history of Russia, found that the interpretation of the history of Ukraine in the context of Turner's thesis is the youngest comparative frontier line, on the example of church leader Gabriel Kostelnyk demonstrated how traditional frontier ambivalence worked even in the XX century even in Galicia. Scope of application: in the process of study of world history, the history of Ukraine, historical geography, regional history, American, Australian, Canadian, Russian, Ukrainian historiography.
