Abstract: Most traditional probabilistic key management schemes of wireless sensor networks have disadvantages of low connectivity, poor resiliency against node capture, and high energy-consumption. A key sharing model is proposed based on (q,l )-threshold secret sharing. In this model, a key is divided into shadows to be shared by virtual cluster heads and re-constructed by the physical cluster head. For tiny cluster member nodes, this model is optimized in improving their resilience against node capture attacks and saving the energy consumption. At the same time, the cluster head nodes properties of security, tolerance and efficiency can be adjusted by controlling the parameters of q and l . Both theoretic analysis and the experimental results prove that, this model improves effectively the resilience against nodes capture attack and the network connectivity, and decreases the nodes overheads.