LEACH(Low-Energy-Adaptive Clustering Hierarchy) protocol was originally designed to reduce and balance the energy consumption of the network. However, the distance between member nodes and cluster head node is not considered, which leads to uneven cluster distribution and uneven energy consumption in the network. Selecting cluster head nodes without distinction is also a problem. Based on the original algorithm, modified LEACH protocol is proposed which fully considers the problems existing in the network, reasonably solves the number of cluster heads in each round, and takes energy as a weight factor into account in the cluster head election. The improved algorithm extends the life cycle of wireless sensor networks, makes network energy consumption more balanced, and improves network performance.