The main aim of this study is to investigate the readiness rate for implementing the 5S methodology in one of the greatest ancient public libraries in Iran and the Islamic world. The other objectives of this study are to determine the necessity and possibility of the 5S implementation in this library. The target population included all librarians, 110 people, working in the library departments who are in direct contact with users, out of whom 86 ones were selected randomly. After holding a training workshop on 5S, required data was collected by a self-made questionnaire. The research findings show that the librarians have a superb knowledge regarding the necessity of implementing the 5S in the library and according to them, implementing the 5S is relatively possible. Moreover, the library readiness, for implementing the 5S, has been discussed.