OA system is one of key technology for college information construction and has important significance. Based on the real demand of college working on digital campus, the functions for college OA system are analyzed, such as official document processing, meeting management, information publishing, individual office, schedule management of leader, and transaction processing. According to the features of OA system, the system design is selectively summarized, including the design of system structure, design of security, design of compatibility. According to the actual application in college, some typical techniques in the implementation of college OA based on web are simply introduced, such as workflow, security, vestige reservation, electronic seal and office reminder.