Because of today's rapid growth of digital contents market and many benefits of electronic book, many people have considerable interest in E-book. Furthermore multifarious consortiums take an active part in standardization of I-book, and many E-book tools have been provided by software manufactures all over the world. E-book tools include editor for production of E-Book, viewer for reading, and the like. Especially in E-book viewer, annotation function has to be Included to put arrangement, summation, recording, comment, emphasis and after comprehension to practical use. In this paper, a E-book viewer with annotation is designed according to the specifications of EBKS, Korean standard. The proposed viewer is aimed to implement in PDA with embedded Linux, but developed in Windows 2000 platform. Because development environment and application environment are different each other, Qt-Library and cross-compiler are used for cross-platform development. The viewer support various functions such as adjusting of font size, hypertext linking, retrieval of specific word, and so forth. And in addition to these basic functions, annotation function is designed for the viewer, which can be used for re-usage and sharing of important information.