Clustering technology used in routing protocols can reduce energy consumption and prolong the lifetime of wireless sensor networks. Cluster head selection is one of the most important parts in clustering routing. An Energy Prediction based selection method based on LEACH (LEACH-EP) is proposed in this paper. Its core is to maintain the structure of clusters unchanged in K rounds. In the first round, cluster heads are selected according to LEACH, and then selected based on energy prediction in the remaining K-1 rounds. LEACH-EP reduces the updates of clusters’ structure and delays the dead time of nodes. Theoretical energy consumption analysis proves the effectiveness of LEACH-EP. Besides, the simulation with OMNeT++ shows that LEACH-EP delays dead time of the first node efficiently and it achieves an improvement on the effective network lifetime. At the same time, it is more conducive to energy balance.