Moral injury is a kind of psychological and physiological trauma caused by the deviation of anti?moral behaviors and events from the moral principles held by individuals or groups. Since it is a complex concept， involving ethics， culturology， sociology and other disciplines. In the disaster situation， facing the complicated situation such as the changeable epidemic situation， high infection rate and large number of patients， medical workers are easily in conflict between internal ethics and external moral practice， and thus fall into a moral dilemma. Once the moral choice made in this situation triggers the unpredictable consequences， it is easy to cause moral injury to the individuals. Based on this， we should help medical workers strengthen the confidence to overcome the epidemic， discard the wrong moral cognition， enhance the moral resilience， and keep good moral psychology.