Abstract: Special collections are gradually becoming the core of library resource development and one of the key indicators of library comprehensive competitiveness. Starting from the evolution and development of the concept of special collections, this paper points out that the connotation of special collections has evolved from “old special collections” to “new special collections”. Combined with the relevant special collections research results since 1982, it comprehensively reviews the domestic special collections research in the past 40 years from the perspective of content, technology and service, and focuses on answering the questions of what special collections are, how to develop special collection resources, how to apply digital humanistic technology to the development of special collections, and how to develop special collections services. It also summarizes the research implications with working practices, aiming to promote the progress of special collections research.