Abstract: An investigation shows the lack of engineering change management(ECM) in enterprise alliance. In this paper an enterprise alliance ECM model is proposed. The model defines the ECM related information of BOM, project management and workflow management with distributed product data management, and describes the integration procedure of distributed resources and workflows in enterprise alliance. Workflows integrate under the resource planning and the detection of a conflict resource set with the procedure, and through the engineering change business process a high efficiency of re-engineering is achieved.