Objective To explore the application of severe simulated cases in the competency training of intensive care physicians. Methods Physicians who underwent standardized training for residents in the Department of Intensive Care Unit, Peking University Third Hospital from July 2016 to January 2018 were randomly divided into a simulation training group and a regular training group, and passed assessment (case analysis and theory) and questionnaires. The way of the survey is to compare the differences in the competency of the resident training positions between the two training methods. Results There were 55 simulated training groups and 48 regular training groups. The simulated training group scores were higher in the clinical basic ability, mastering and applying medical knowledge ability, team cooperation ability and information quality than the control group, and the differences were all statistically significant (all P<0.05). In terms of case examination, the clinical basic ability, doctor's professional spirit and quality, mastery and application of medical knowledge, teamwork ability and information quality of the experimental group were higher than those of the control group. The differences were all statistically significant (all P<0.05) ). Conclusions Severe simulated cases are better than conventional training methods for the training of resident positions. It is worth learning and promotion.