Effective information strategy and information systems are important for the development of automobile manufacturing enterprises. In complicated and dynamic business environment, information systems planning (ISP) faces the problem of lacking integrated optimization of enterprise strategy, business strategy, and IT strategy. A hierarchical information system planning model is developed for automobile manufacturing enterprises. A planning approach is proposed to make the information system continuously mating the enterprises' strategy. The proposed studies were applied to agile ISP of an automobile manufacturing enterprise with satisfied result.