[Purpose/significance] Under the background of big data,this paper aims to explore how governments use big data to assist the innovation of emergency management.[Method/process]Through the methods of literature analysis and comparative analysis of cases,the paper summarizes the advantages of big data applying to governments' emergency management,analyzes the differences among governments' emergency management of China,US and Japan,and gives enlightenments on the innovations of our country's emergency management.[Result/conclusion] In order to make the better use of big data in government emergency management,the paper proposes to construct a collaborative innovation system,which includes the tools,system construction,application fields,personnel training,supporting facilities,publicity and education of big data.[Limitations] The suggestions of this paper need more practices to verify.