The article aims to clarify the structural and conceptual peculiarities of training teaching staff for the US adult education system. A set of interrelated research methods such as classification and systematization of data, structural and functional, comparative and educational, interpretive and analytical analysis is used. It is found that training teaching staff for adult education system is implemented in fifty USA universities. It is revealed that the USA universities mostly offer one or two training programs, Master of Science and Doctor of Philosophy being the most numerous ones. It is noted that enrollment in adult education programs is conducted in accordance with the concept of «whole person» that is based on life experience, prior learning recognition and motivation to learn. It is found that the greater part of training programs for teaching staff of adult education is offered remotely. The most common is distance learning which is carried out by individual universities. The main features of training programs are allocated: the right to choose from a wide range of programs and disciplines, an opportunity to gain experience by participating in various projects, to use the latest equipment and technology, to combine active targeted training and professional development, project and problem-based learning that lead to sustainable improvements in adult education. The possible options for successful completion of programs, such as thesis, exam or project are revealed in some universities. The structure of doctoral programs which consist of a course of basic and optional subjects, dissertation research, exams and defending a thesis is analyzed. It is stated that the Doctor of Pedagogy program is more practically oriented. Certificate programs are designed to obtain certification for those looking for more specialization in adult education or further study for a master’s degree. The study does not cover all aspects of training teaching staff for adult education in the United States of America. It is offered to conduct further investigations of alternative assessment, development of distance learning programs and project-based learning in training teaching staff for adult education system.