At present,most of the improved?protocols based on LEACH (low energy adaptive clustering hierarchy) start from the aspect of cluster head election, cluster distribution, path selection, etc., but the redundancy between the data is not considered enough. This paper proposes an improved LEACH protocol combining relative information entropy (LEACH-CIE). Combined with the relative entropy model, this paper calculates the relative entropy value of the probability distribution of the data of the two adjacent cycles of the node, and then the relative entropy value is compared with the threshold to judge the redundancy of the data. By rejecting the transmission of redundant data, the purpose of reducing network energy consumption is achieved. In the data send stage, considering the communication distance, energy consumption ratio and other factors, a multi-hop forwarding routing considering its own residual energy (MFRCRE) is proposed, which can optimize node forwarding conditions and balance the energy consumption rate of each node in the network. Experimental results show that the method in this paper can effectively reduce and balance the energy consumption of network nodes to extend the network life cycle.