Abstract: Difficult cases have complex etiological factors, diagnosis, and treatments in the process of clinical work, which not only bring great pain to the patients, but also trouble the doctors for correct diagnosis and treatment. Improving the level of diagnosis and treatment of difficult cases, will not only help patients to relieve pain, but also promote the level of medical treatment of clinical departments, which has a positive role in the resident training. In the process of resident standardization training, the teaching based on difficult cases discussion is a feasible and effective method.