Analyzing the Stable election protocol (SEP) in wireless sensor networks and aiming at the problem of network structure as, unbalanced nodes distribution per cluster, random deployment of advanced nodes. unreasonable cluster-heads selectivity and undefined time period in which the nodes to become a cluster head. So, an optimal energy leach protocol (OLEP) is proposed. In this algorithm, the network structure constructed by using Voronoi tessellation, thus the balanced nodes deployment. Based on SEP, the node's residual energy is added in cluster-heads election. The information is transmitted with mode of multi hops between network nodes. The simulation experiments showed that compared to the classical LEACH and SEP, this algorithm balances the energy consumption of the entire network and significantly prolongs network lifetime.