In this paper, a social network model based on real social relationships, referred as Relation Grid, is proposed. Relation grid is isomorphic to the actual social network; hence it can represent the actual social network well. It is discussed that the proposed model is pure distributed, scalable, self-adaptive and selforganized. The application perspective of relation grid is encouraging. It not only provides a new way to acquire social relationships, but also can be used as an underlying background to construct online communities and organizations.