Enterprise managers must formulate correct strategic decisions rapidly because of the increasing complexity of management environment. The article analyzed the concept connotation and the development of big data. Integrating real cases, the article also analyzed how big data providerich data sources for enterprises'strategic decisions, and how it can improve the quality of strategic decision making. It also demonstrated the support function of big data in upgrading strategic decision makers'insights. Finally the article proposed some problems and relevant suggestions of big data during its developing process.