The implementation of bureaucratic reform in government is accelerated by the implementation of e-government technology. Sekretariat Direktorat Jenderal Bina Upaya Kesehatan (Setditjen BUK) uses a manual office administration system. It requires a lot of office stationery supplies, time, and energy to process documents to distribute. Another problem is that searching for documents is difficult. The research objective is to build an incoming mail and outgoing mail data processing system that can convey information in detail, briefly and clearly, easy to understand with an attractive appearance. The data collection methodology used is observation by looking directly at the workings of the sections related to recording the results of activities, and also seeing firsthand the system that works in e-office data processing. In addition, the interview method is used to find out the problems that arise or are experienced by research sources. The result is the design of incoming and outgoing mail data processing applications with complete information delivery according to user needs.