Continuous advancement in wireless communication has enabled the deployment of wireless sensor networks for environment monitoring. The use of wireless sensor networks in this type of monitoring, it is very much difficult to replace the battery of the sensor node or replace whole sensor node once they deployed. So that development the different methodology to extend the lifetime of the sensor node is must.Low Energy Adaptive Clustering Hierarchy (LEACH) is cluster based routing protocol which provides life expectancy. In this paper proposed new routing protocol Energy Efficient Hybrid LEACH (EH-LEACH) in which the threshold criteria for selection of cluster head is changed and also consider residual energy of the sensor node. The simulation results clearly indicate that proposed approach is very much energy efficient as compared to LEACH. Also EH-LEACH is sustaining his properties while varying node density. Optimization of cluster based hierarchical routing protocols is required for Better Operations. General TermsTwo ray model, Cluster head selection algorithm, Steady state phase, Threshold Criteria,Sensor nodes.