Abstract: The patent analysis and patent application system is surveyed in detail. Then a tree model is proposed to describe the patent document. Based on this tree model, massive patent documents can be sorted with a vector space model and the correlative patents can be searched. The method is a new way to integrate patent management system with enterprise application system. Finally, a patent management system is integrated with the workflow management system, the integrated framework is built up and the integrated system is developed. And the patent management system can be used in the unit of workflow system; this system is used successfully in designing an electric retarder.