In this paper, the industrial cluster upgrading is interpreted based on innovation ability. According to knowledge and social relations level, cluster upgrading is converted into the supernetwork interacted with social, explicit knowledge and tacit knowledge network. By using the relationship between variational inequality theory and optimization problem, the flows h*ij、q*eij、q*tij among explicit knowledge network, tacit knowledge network and social network are obtained, and the equilibrium of cluster supernetwork is also achieved. The change of flows in network and equilibrium of cluster supernetwork caused by alteration of cluster size, number etc are approached. The cluster upgrade is realized in unceasing variation of equilibrium. Finally, practical significance of interaction among network is illustrated based on case and further research direction is pointed out.