This paper studies the wireless sensor network time synchronization technology for sensor networks with limited energy, we proposed an energy efficient time synchronization algorithm EETS (Energy Efficient Time Synchronization). It uses a hierarchical clustering strategy, divides the network into two different subnets, respectively TPSN algorithm and idea of the DMTS algorithm for time synchronization, thereby reducing the complexity of the algorithm, reducing traffic. Simulation results show that, compared with the TPSN algorithm, this algorithm reduced the energy consumption of the network, effectively extended the network life cycle.