Abstract: Supply Chain (SC) is a new relationship pattern among enterprises, and Supply Chain Management (SCM) is for this relationship essentially. Only after the research of this relationship is deeply done can the problems existing in the development of SCM be well solved. In this paper, a model for joining in SC is established with the knowledge of game theory for the first time. The correctness and applicability of the proposed model are proved through computation and validation, and many fundamental questions and characteristics of SCM are scientifically explained based on the model. The work of this paper is to provide a new way for the research of SC and SCM.