Abstract: In recent years, unconventional emergencies occur frequently. Due to its characteristics of unpredictability, complexity, and small probability events, conventional "Prediction - response" model has been difficult to effectively deal with unconventional emergencies. "scenario - response" is a basic paradigm to deal with unconventional emergencies. Based on this background, research on scenario and scenario-response theory of unconventional emergencies has become a hot point in the areas of emergency management. Review on present literatures can sort out the direction of future research and it plays a positive role in promoting the work in unconventional emergency management.