In order to solve the wireless sensor network MAC layer idle listening, conflict and control overhead to bring invalid power cost, a new energy-efficient wireless sensor network MAC dynamic new method of non-decile slot is proposed. Based on the type of network topology and monitor the coverage analysis model, a dynamic voting algorithm is designed by election minimum residual energy code. One-way broadcast of the cluster clock synchronization algorithm ensures network nodes having the same time reference. Based on wireless sensor test bed the simulation experimental results show that the method has the good protocol functions which adjust the number of nodes and non-decile transmission slots dynamically, and significantly improve the energy efficiency of the MAC layer. The method can effectively use a network of energy and prolong the network life cycle, which is an energy-efficient MAC protocol for wireless sensor networks.