The invention provides an unmanned vehicle emergency avoidance decision-making system and method and a medium. The system comprises an environment perception module which obtains environmental information; a danger judgment module which analyzes whether there is collision danger between the vehicle and the obstacle according to the obtained environmental information, outputs the danger state information, judges the obstacle category and outputs the obstacle category information; and an intelligent decision-making module which constructs a feasible task pool according to the obtained environmental information, the danger state information and the obstacle category information, analyzes the accident severity of the feasible task and determines the optimal feasible task. The system has the convenience in application and can be compatible with the current intelligent decision-making scheme for vehicles under no accident. The system can provide a decision scheme for minimizing accident damage when a vehicle is faced with an inevitable accident.