Mobile Adhoc networks (MANET) enable mobile nodes to communicate with each other over wireless links without any centralized controller or base station. In MANET, each mobile node powered by the battery. Hence, efficient utilization of battery energy is a key factor. Optimized Link State Routing (OLSR) has been accepted as one of the distinguished and dominant routing protocols for Mobile Ad Hoc Networks. OLSR uses a concept of the Multipoint Relay (MPR) selection mechanism to reduce the broadcast packet during a flooding process. In OLSR protocol, MPR nodes use more energy than nonMPR nodes. Due to this MPR nodes run out their energy. In this paper, we have propose a novel energy efficient routing method in OLSR protocol by modifying its MPR selection strategy to improve the networks lifetime in MANET in terms of energy. All simulation will be performed in NS2 with OLSR routing protocol.