Information explosion and evolution of new technology brought great impact on the library development. The library services have changed a great deal from a mere book-stack to the readers oriented services. The library instruction, in this case, becomes more and more important. Unfortunately, the aspect has been ignored and lack a systematic planning in the teacher colleges. This paper is trying to find out a way that could implement a set of reader orientation program to promote the library services among the universities training the future teachers. In the beginning, the author has looked through the references in this subject area, concluded a definition and goal for the "Library Instruction", then trying to find out the importance and its relationships between library instruction and teaching, and then talked about the three steps of library instruction, pointing out the focus on readers' needs when designing the content of the instruction program. With the practical example from the National Taiwan Normal University Library, it indicates the influence that the network development has on the library. And this paper brings out two suggestions, firstly, the on-job training for librarian, and secondly, the need for a standard working instruction manual. Finally, it concluded that library service is a kind of marketing and it provide the right kind of knowledge to the proper reader, and making the readers a real information users is the goal of the library instruction.