This final year project discusses the development of a web application tftat assists the business processes at Comic Zone book rental. Comic Zone is a book store that rent a variety of books. This web application is built to overcome the limitations of the current manual rental process. The current process of book rental does not have a specific procedure. Budget estimation and registration to become a member are still done manually. Because of this, the current process is prone to human erros and experiences numerous delays. The proposed system intends to overcome these problems. The development of the web app consists of several phases: analysis of the current system, requirements gathering, design, and construction. The methodology used to develop the proposed computer-based application is Rapid Application Development (RAD) with evolutionary prototyping method. The proposed application is built using PHP and Microsoft SQL Server 2008. The application development project is modelled using UML version 2.0 which includes use case diagram, activity diagram, and class diagram. Application testing is done using black-box testing with scenario and functional testing. The proposed system facilitates customers to rent and/or reserve books online. Customer can see comments and review from the customers that have previously rented the books. This application can also record the rental history of customers (what books he/she had rented, the prices of those books, and when they were rented).