In the article the influence of progressive philosophical concepts on the development and formation ofadult education in the USA (neo-behaviourism,liberalism,progressiveness,reconstruction, technocracy, radicalism, humanism) has been analyzed. There have been considered the importance and actuality of American scientists’ approaches to the problem of adult education andproved their necessity and urgency. The key principles of adult education have been identified (humanization, democratization, freedom of choice, flexibility, continuity, taking into account the experience of individualization, differentiation). Particular attention is focused on the structure, objectives, functions, types of adult education, strategic directions of its development in the late twentieth and the beginning of the XXI-st century. Having studied the official documents and statistic data of international organizations on the problem of adult education, there have been revealed common approaches (the main strategies of perspective development of adult education, diversification of financial sources, human sources investments, providing the lifelong education for all, improving the legislative framework, working out the flexible educational programs and innovative teaching technologies, ratification of non-formal and informal adult education, stimulating perspective projects on the problem of adult training) to the solving of the problem. It has been established that the modern system of adult education based on a symbiosis of ideas in a complex capable of substantially change its main goals and objectives in accordance with social demands of American society. Despite the different views of scholars, adult education is seen as a process that is performed during life, the purpose of which is to create conditions to meet the educational needs of adults as well as opportunities for further professional development, mobility, efficiency and effectiveness of their life. It has been proved that the system of adult education in the USA is an open, independent, flexible, multifunctional, diversified, adaptive structure, which covers interrelated and interactional components (legal, national, technological, diagnostic, personal, administrative and correctional). The author has concluded that the development of adult education in the USA depends on internal and external determinations such as: globalization and integration processes, dynamic changes on labor-market, information technologies development, educational reform, and the main trends of public policy.