Big data shows us the development direction of the Internet. The studies on the application of big data can provide an effective way for the government to upgrade public management and public services. The purpose of this article is to explore how the big data applications improve the efficiency of the government emergency management from the connotation of the big data and the present situation. At the same time, in the application of big data, it is also important to pay attention to the protection of data security, to improve the privacy policy, and to keep the balance between public safety and citizen privacy.