This article utilizes case study research approach and business process reengineering to investment changing request forms and request flows. This study discuss about changing document flow from paper operation to electronic operation in the way of business process reengineering and information science technology support to establish official document flow electronically. It will improve the traditional transmission of document flow of paper, promote the change service efficiency of the information technology department, and handle even more large amount and change the request quickly. According to the study, after interviewing the personnel of all departments of case companies, there were three serious consequent shortages about the paper document flow. First, paper forms would take a lot of time to roam around in the flow. Second, the official document has been lost out of the flow. Third, tracking signing information is impossible at that time. At the end of the case, it would be able to find out the corresponding solutions to every question respectively.