Against international background，how to respond to emergencies is an important issue that the government should face. Government discourse is performing an essential part in the process. Strategies utilization produces a significant effect on the development direction of emergencies. The present research is an attempt in following this guide by combining theory with practice，making use of our own language resources and comparing Chinese and American governmental discourses from a multidimensional and interdisciplinary perspective. This study takes critical discourse analysis as its methodological basis，and English-Chinese comparison and corpus-based research as its interest research perspectives.

In dealing with emergencies，official speech played a very important role. Language strategies can have a major impact on the direction of emergencies. The main carrier of government’s official discourse spread is mass media. From the perspectives of political science，international relations and linguistics，this article sorts out the origins，basic methods，and status quo of official discourse in public emergencies，and uses critical discourse analysis and metaphorical rhetoric as research methods. Finally，the article expounds the application of comparative research and corpus-based quantitative analysis methods.