In the manufacturing of diesel engine, cutting machining is the main processing method. In order to improve efficiency and increase benefit of machining, the cutting database and parameter optimization system is built for the five key parts of marine ship diesel engine, which can provide optimal and rational cutting parameters. Microsoft Visual Basic and Microsoft SQL Server 2000 are used as the database management system, combining the modeling function of Deform 5.03 software. The logical and physical models are designed, and the functions of basic information management and query are realized. It can commend reasonable cutting parameters according to machining condition input. The Weilenmann algorithm method is adopted to calculate the cutting force and motor power, and user can be convenient to judge whether the parameter input is safe and reasonable. The objective function and restrictive conditions are set up by using the simplex method and linear programming, and the optimization function of cutting parameters is realized. A developed prototype system and an example have verified some presented techniques and the research results are the basis of the future development.