Taphozous melanopogonandT. l. longimanus(family Emballonuridae, have 2N=42,Megaderma I. lyra(family Megadermatidae) has 2N = 54 andHipposideros fulvusandH. a. ater(family Hipposideridae) have 2N=32. The chromosomes of Megadermatidae and Hipposideridae have been studied for the first time. Interrelationships on the basis of available chromosome data and also the probable mechanisms of karyotype evolution in these Indian species of Microchiroptera are discussed.