Based on the types of computers used in the library automation, the integrated library systems in this country are classified as multiuser-microcomputer systems microcomputer based LAN systems and middle-sized or minicomputer systems in this paper. Three examples of practical systems are used for the analytic and comparative study on the eight aspects such as system goal and practice, integration, data sharing, implementation techniques for bibliographic database, and multilingual processing. A comparison table on the performances and system functions of the three models is given in order to help the users in machine selection and system implementation.