In the twentieth century Ukrainian libraries were an important link in the chain of development of the Ukrainian state. The short period of the Ukrainian National Republic's existence (1917–1921) showed that libraries were aimed at solving extremely important and urgent tasks of national youth education.Ideological changes took place in the nature, purpose, content, and organization of libraries' cultural and educational work.The purpose of the article is to study the genesis of the development of libraries in Ukraine in the 20th century, to determine the influence of historical and socio-political factors on their activities. The scientific novelty of the proposed work is changing of approaches to the assessment of library activity as a tool of ideological influence on the education of youth and the population of Ukraine in the 20th century as a whole.The library, as a cultural institution, has gone through a difficult path, in which the forms, methods, directions, and functions of its activity have changed due to the relevant social need. As an important component of the social system, the library reflected society's desire to realize its requests and value orientations.The activities of the libraries were aimed at: first, to get acquainted with Ukrainian writers and scientists; secondly, to study the history of the native region, village, city; thirdly, on the development of creative abilities of young people.As you know, the work of libraries was strictly regulated, coordinated by party organizations, subordinated to the national interests of the contemporary society, aimed at solving the tasks of building socialism, communism according to the prevailing ideology of Marxism-Leninism.After the end of the Second World War, one of the main tasks was: first, to analyze the condition of existing collections; second, to determine the ownership of libraries; third, to organize the assessment of losses; and fourth, to record destroyed or damaged library premises.An analysis of the activities of libraries in the 50s and 60s of the twentieth century shows that special attention was paid to the mass-political work of libraries. Excessive attention, in our opinion, was paid to the creation of the thematic bibliographic apparatus, which contributed to the wide coverage of readers in getting acquainted with Marxist-Leninist literature.During the years of development of the Ukrainian state, library workers made a significant contribution to the revival of Ukrainian culture, history, and traditions, the forms of work with visitors to popularize cultural values diversified.Therefore, the study of the genesis of the development of libraries in Ukraine in the 20th century at various stages of the cultural and historical development of society proves that their activity was greatly influenced by historical and socio-political factors, under the influence of which their social role and social purpose changed. The analysis of historical processes taking place in Ukraine shows that they had a direct impact on the nature, directions, forms and methods of library work. The declaration of Ukraine's independence in 1991, the democratization of public life dramatically changed the social role of libraries as cultural institutions, contributed to the restructuring of the forms and methods of their activity, the transition to new conditions for providing services to the population.At all stages of its activity, the library is an important body that accumulates various types and forms of knowledge dissemination, provides a unifying function of information about education, culture, upbringing, art, ensuring the interaction of pedagogical, educational, cultural and self-educational activities of each individual.Thus, the phenomenon of the library as an institution is that during the twentieth century, depending on historical and socio-political factors, it went through several periods of development, changing its status, directions, forms, methods of work, content and principles of activity, social role, and performs an important mission in the revival of Ukrainian culture, development of education and science.This study does not cover all aspects of the identified problem and requires further research into the genesis of the development of libraries and their educational activities.