The public library needs to be a main research library and information center concerning its own locality. So it is the duty of the public library to collect, organize, preserve local documents collections in order to be uetimdely used by patrons. This article mainly comprises five sections: public libraries and the acquistions of local documents collections, public libraries and organii- zations of local documents collections, public libraries and the preservations of local documents collections, public libraries and the services of local documents collections, the cooperation of public libraries and other institutions on local documents collections. The author regards it is a meaningful issue to discuss the relationship between public libraries and the local documents collections.