The purpose of workflow mining is to build proper model based on event-based logs and to support the analysis and design of workflow models. The workflow mining technology had become a hot research field among computer application from the late 1990's. Firstly, the definition and research significance of the workflow mining are presented. Then, we made an overview of the current workflow mining technologies including the origin of workflow mining, the mining of the workflow models, the mining of the workflow performance and the improvement in workflow models based on the workflow mining technology. Finally, the facing challenge and the development direction of workflow mining are presented.