With strong unpredictability,social security incidents have been ineffectively managed by conventional prediction methods. The "scenario-response" model has become an effective method of emergency management dealing with social security incidents in universities and colleges. Therefore,it is of importance to study the mechanism and process of scenario evolution. In this paper,the authors conducted structural description on emergencies' framework based on multidimensional arrays,analyzed the dynamic factors,internal mechanism and explicit mode of the scenario evolution,and then carried out research on the status and result of scenario evolution and development of the social security incidents in universities and colleges under multi-scenes with the example of a certain group conflict. The research showed that:social security incidents in colleges and universities are strongly situation-dependent. The strong correlations between various scenario subjects,scenario elements and scenario chains of different incidents form different scenario evolution. The paper put forward rational proposal for universities and colleges to respond to social security incidents,and provided theoretical support for the construction of emergency preparedness system for incidents.