Abstract: The traditional C/S database systems often suffer from the poor performance in the environment of Web applications because the number of users and the frequency or the times of accessing to a Web application are very difficult to be determined in advance.In this paper,a new method is proposed for the design,implementation and tuning of the Web based database system.This approach focuses on the configuration of RDBMS,the design of application model, and programming.By optimization on memory,on fragmentation,on disk parameters and on time related parameters,a better running environment of RDBMS can be set up.By reducing the CONNECT and DISCONNECT operations,creating suitable indexes,using more stored procedure and optimization on SQL,good performance can be got at programming step.By optimization on business logic and denormalization,the system performance can be greatly improved at design step.