The research on the Social Service Department (SSD) of Peking Union Medical College Hospital can be divided into two periods: the period of the Republic of China and the period after the founding of the People’s Republic of China. During the period of the Republic of China, most of the researchers had worked or practiced in the service department, and their research results were of the nature of work summary and method discussion, with strong instrumentality and practicality. Since the 1980s, Marjorie King, an American scholar, began to conduct in-depth research on the history of SSD during the period when Ida Pruitt was the director, and the Japanese scholar Yamaguchi Mamoru has also been committed to the research on the formation process of Pruitt’s cultural identity for a long time. After the founding of the People’s Republic of China, there was once a completely negative attitude towards SSD in China. After the reform and opening up, the research started slowly from scratch and developed rapidly after the new century, which not only highlighted the professional perspective, but also showed an integrated research trend.