Wireless Sensor Networks (WSNs) are increasing to handle complex situations and functions. In these networks some of the nodes become Cluster Heads (CHs), aggregate data of cluste members and transmit it to the Base Stations (BS). However, homogeneous networks are no enough efficient in consuming energy. Hierarchical Stable Election Protocol (H-SEP) introduces heterogeneity in WSNs, consisting of two type of nodes: normal nodes and advanced nodes HSEP is based on weighted election probabilities of each node to become CH according to remaining energy of nodes. We propose heterogeneity aware hierarchical routing protocol i.e Stable Election Protocol. The impact of heterogeneity nodes, in terms of their energy, in wireless sensor networks are hierarchically clustered. All simulations are done in MATLAB. Different parameters are used for checking the efficacy of the considered routing protocol for H-WSN. Simulation result shows that SEP considered with parameters such as alive nodes and dead nodes etc. has better performance as compared to other protocols. MATLAB Simulation results show that H-SEP prolongs stability period and network life time with respect to number of alive nodes, percentage of dead nodes & energy consumption ratio for total number of rounds.