The usage of sensor networks is rapidly growing due to their small size and easily deployment. It means that we can easily expand and shrink such network, so sensor networks are more flexible as compare to the other wired networks. Due to this flexible nature such network has many applications in various fields. Object tracking is such one of the most important application of sensor network. Wireless sensor networks are Ad-hoc networks which contain a set of nodes which have limited computational power and limited power resources. As the energy resources are limited in the sensor node so full utilization of the resources with minimum energy remains main consideration when a wireless sensor network application is designed. Power is supplied with the help of batteries fitted with the sensor node and is not easily replaceable. As energy is one of the major components of such network, so we take this issue for further consideration. In order to maximize the lifetime of sensor networks, the system needs aggressive energy optimization techniques, ensuring that energy awareness is incorporated not only into individual sensor nodes but also into groups of cooperating nodes and into an entire sensor network. In this paper we suggest an energy saving scheme called Maximize the Lifetime of Object tracking sensor Network with node-to- node Activation Scheme (MLONAS) in which minimum number of nodes are involved in tracking of an object while other nodes remain in the sleep mode. When an object is going to enter the region of other node it will activate that node and when that node start tracking the object previous one will go to the sleep state. This scheme can increase the life of sensor network as few nodes are involved in tracking of moving object where as others remain in the sleep state.