Aircraft maintenance management directly affects the aviation safety and the operating cost of the airline company. Aircraft maintenance management task must follow the standard operation procedure and the task is both complicated and stressful for the maintenance personnel. Furthermore, the various levels of the maintenance managers need different information of the maintenance management, so they could make correct and quick decision The advantages of using Object-oriented Decision Support System there are the maintenance management tasks been understood easily, constructive maintenance processes, and easily modifying the database that would satisfy the maintenance managers' requirement and promote the maintenance efficiency. In this study, maintenance management records of the Uni Airline would be used and a maintenance management decision support system of the aircraft would be structured for the maintenance management department of the airline company to provide maintenance management information including total maintenance cost, standard maintenance task process, the optimal combination of the maintenance personnel, and the reliability of the maintenance management.