Currently, the system of borrowing and returning books in SMKN 1 Kotabumi still use manual bookkeeping for the transaction process. In addition to the process of adding data from members of the library is also still using manual bookkeeping for the addition of data member. The purpose of this research is to make the application of information system of desktop based library management to assist the addition process of member data, book, as well as transaction of borrowing and return of book. In this research author used Software Development Life Cycle (SDLC) method. From the test results BlackBox Testing has done, it can be concluded that the application of School Library Management Information System has met the purpose of research and can be used well, as evidenced by the way the application functions well.