This article systematically reviews and sorts out the development process of adult education of library science in the 70 years since the founding of New China. According to its different characteristics in different stages of social development, it can be divided into three stages: The stage of rise and initial development from 1949 to 1977；the stage of rapid development and unprecedented prosperity from 1978 to 2000；the stage of transformation and upgrading since 2001. The article summarizes the achievements, characteristics and laws of adult education in library science at each stage. The author thinks that the direction and path of the development of adult education of library science in the new era is to broaden the horizon and face the broad social information profession; "Adult education" should turn to "continuing education" and develop postgraduate education steadily.