For the second-hand trading system, the interface design, function design and data should be further improved, while giving users a good sense of experience. Through this system, all the second-hand goods can be displayed, students can quickly query all the second-hand goods, users can modify their personal data at any time, and realize the function of online purchase of second-hand goods. In order to give users purchase suggestions, the system provides a sales ranking to help the system do a good job in marketing strategy, and the administrator can operate all the information in the front desk Maximize the realization of easy maintenance and easy operation, through the simplified operation of the database, make the system run stably and smoothly.