Connectivity is the guarantee of network communication, and connective equilibrium is an important indicator of the network connectivity. With the frequent changes of topology of opportunistic sensor network, the traditional graph model is not applicable for modeling opportunistic sensor network. This paper aims at how to accurately depict the connective equilibrium degree of opportunistic sensor network. The contribution degree and clustering coefficient of Ferry nodes are defined, and connective equilibrium degree is defined as well, which can reflect the connectivity balance of the network. The connective equilibrium model of opportunistic sensor network is proposed based on the temporal varying graph. The simulation results show that the proposed model can reflect the connective equilibrium of the network. Furthermore, it can provide an effective support for exploiting involution and maintenance of opportunistic sensor network.