Abstract: Case method, which can simulate the real situation, solves the problem of the disconnection between the theory and practice of classroom teaching to a certain extent, and is an important means to cultivate the professional ability of professional degree graduate students. Since the introduction of case method, researchers in different disciplines have deconstructed and analyzed different aspects of case method. By using the method of literature analysis, this paper systematically analyses the origin, development and communication of case method, the comparison between case method and traditional teaching, and the important organizational form of case method. On this basis, the following understandings are proposed: according to the origin of different opinions, it is further clarified that Harvard Law School is the birthplace of modern case method in the United States; the evaluation of traditional teaching needs to be specifically differentiated in combination with the application orientation of professional degree graduate education, which cannot be generalized; Harvard case method needs to be localized and adjusted based on China's national conditions, and visiting case method should be optimized from the aspects of instructor, visiting case, visiting reception unit and support of departments.