Abstract: Although the revised Chinese Library Classification (fifth edition) supplements many new topics and new concepts,adds some composite marks, enhances class’s accommodate and division depth,which makes the classification more science and practicability,there are insufficient,such as the level dim of category setting,insufficient clear of class name and note concept ,the lack of category setting system,etc. It gives some specific modification measures aiming at problems,and points out the development direction of Chinese Library Classification by comparing Chinese Library Classification (fifth edition) with others classification systems.

Key words: Chinese library classification, library classification, category setting