Data library Circulation System SMP Negeri 1 Sewon Bantul is one of the data processing activities that provide information services for both existing parties in the institution and outside parties relating to the institution. Hopefully, with good library management, and processed in such way can produce the right information, quickly and accurately. In this regard the computer as a media electronic can help the data processing activities (which was previously done manually). Including with the making of the reports, and of course would be more efficient in terms of time the data collection process. Therefore, the data library circulation system will be developed into a computerized data processing system.