Liceo de Cagayan University library offers Online Book Access Catalog (OPAC) system to aid library users in searching for the books they need. Though OPAC gives a satisfactory service to cater to the needs of the librarians and the library users, its services are limited to book-monitoring and book-availability. One major concern of the library users is to queue up their reservations when the books they need are not available (e.i. somebody has borrowed the book already). This study is intended to address the necessity of creating an Online Book Information System (OBI) to solve the problem on book reservation. The system was designed to run via the internet for a more sophisticated and convenient way of reserving books. In this manner, library users can save travel time visit to the library for a simple inquiry of book availability. The OBI System can be accessed via Liceo de Cagayan University official website as one of the library services and is running under testing phase. Evaluation of the OBI performance and its functionalities maybe addressed for future study.