The purpose of this study is to review the historical development of British Museum Library and its cataloging rules which really marked the beginning of the modern era of cataloguing. The results of the study can be summarized as follows (1) Sir Anthony Panizzi was the most creative force in the history of the British Museum Library. He devoted himself to the formation of the British Museum Library cataloging policy and the compilation of printed catalogues. Moreover, he laid down the sound acquisitions policy and the vigorous a n.0, pplication of the copyright deposit privilege. He designed a great circular reading room and raised standards of library service and administration. (2) British Museum Library Cataloging Rules : 1. are notable for their pioneering efforts-this was the first major catalogue code-and for their influence on all subsequent codes. 2. introduced the concept of corporate authorship but has never dealt with problem very satisfactory. 3. went to great lengths to avoid title entry. 4. used a number of form heading, example for, ACADEMIES, PERIODICAL PUBLICATION, EPHEMERIDES, CATALOGUES etc.