Enterprise Resource Planning (ERP) has been increasingly considered as the base on which enterprises can achieve competitive advantage over their counterparts. However, the outcomes of ERP that have been implemented home and aboard usually dissatisfy what the enterprises need. The implementation of ERP is so complicated that all aspects of business are involved, which makes it a tough and hot topic how to measure the effect of it. ERP is a kind of information system essentially in which management thoughts are embedded. Therefore, on the reviews of overseas studies on complex information systems, we suggest that user satisfaction should be taken advantage to measure the effect of ERP project, which gets it possible to do empirical research in this field in future.