Abstract: This paper presents a framework of enterprise resource planning (ERP) system which is applied to virtual organizations for small and medium-sized enterprises (SMEs). The compatibility between ERP systems and the enterprises in which the ERP systems are implemented is discussed. Furthermore, some special issues on the implementation of ERP systems in virtual organizations are analyzed. According to the features of virtual organizations for SMEs, a framework of ERP system including two subsystems for both core enterprise and member enterprises in an virtual organization is proposed. The collaborative business process among these enterprises in ERP environment is described.