The wireless sensor network is a type of the wireless ad-hoe networks. It is composed of a collection of sensor nodes. Sensor nodes collect and deliver necessary data in response to user's specific requests. It is expected to apply the wireless sensor network technology to various application areas such as the health, military and home. However, because of several limitations of sensor nodes, the routing protocols using in the wireless ad-hoc network are not suitable for the wireless sensor networks. For this reasons, there are many novel routing protocols for the wireless sensor networks is proposed recently. One of these protocols, the PEGASIS (Power-Efficient GAthering in Sensor Information Systems) protocol is a chain-based protocol. In general, the PEGASIS protocol presents twice or more performance in comparison with the LEACH (Low Energy Adaptive Clustering Hierarchy) protocol. However, the PEGASIS protocol causes the redundant data transmission since one of nodes on the chain is selected as the head node regardless of the base station's. location. In this paper, we propose the enhanced PEGASIS protocol based on the concentric clustering scheme to solve this problem. The main idea of the concentric clustering scheme is to consider the location of the base station to enhance its performance and to prolong the lifetime of the wireless sensor networks. As simulation results, the enhanced PEGASIS protocol using the concentric clustering scheme performs better than the current PEGASIS protocol by about 35%.