This study investigated the actual condition of book numbers in South Korean academic libraries. Book numbers that are used in the Korean academic libraries consist of a combination of author-number or author-name, the first letter of the title, and any other shelflisting device. This study examined the current problems that perceive academic librarians on book numbers and the problem awareness of librarians who are working at 110 academic libraries in South Korea. The result shows that academic libraries are using eleven different methods of the book numbers table including nine eastern methods and two western methods. Also, librarians mentioned that the crucial concerns among participating libraries were the duplication of the book numbers and ineffective collection management. Therefore, this study suggested the expansion of the book numbers system in order not to duplicate of book numbers and the unification of western and eastern methods so that academic libraries tackle problems of ineffective collection management.