This article analyse the function of information technology (IT) in the library, in particularly indexing, storage, and dissemination of information. Indexing function of IT in the library as well as copy cataloguing, original cataloguing, bibliographic monitoring, labeling, book card and its properties. IT function in information storage spread used in the CD, diskette, microform, etc. In dissemination of information IT used in diskette, audio visual and network. Dissemination of information through network like internet, LAN, WAn, Expert System, electronic group discussion, scientific group based computer