Insectivorous bats are well known predators of nocturnal flying insects and can potentially play an important role as bio-control agent in agricultural ecosystem at free of cost. The dietary analysis of left outs from the secondary roosting site of Megaderma lyra confirm their role as a pest control in agro ecosystems and keep a check on major nocturnal pest. The left outs from the feeding roost of M. lyra showed their hierarchy in the selection and consumption of major insect order lepidoptera preference throughout the study period from August 2021 to April 2022. The major composition of food item is Lepidoptera which includes moths and butterflies. The larvae of these insects are probably more destructive to agricultural crops. Thus the carnivorous bat Megaderma lyra are the pest managers of agro ecosystem in Tirunelveli.