Bats use a combination of visual, acoustic and olfactory signals to communicate. Breeding behavioural studies in a few bat species reveal that chemical signals from scent glands are involved in communication. Bats possess modified skin glands at distinct regions to secrete odoriferous compounds. The chemical compounds of the scent gland secretion, saliva and urine directly stimulate biochemical reactions. In bats, the integumentary glands empty their secretions outside the animal’s body to expel the odour. These chemical signals aid the bats to communicate and mediate sexual behaviour during the breeding season. The scent-marking behavioural patterns of bats in their roosting sites are categorised as territory marking, settlement of pairs in the marked territory, grooming, fanning, body rubbing, sniffing and mating. The nocturnal and social lifestyles of bats suggest that besides acoustic signals, scent plays a key role in communication to achieve reproductive success. This chapter attempts to bring out the chemical signalling from a few common insectivores and frugivores bats in tropical ecosystems.