Abstract: Grooming behavior is evolved in animals in response to the costs associated with ectoparasites. In this study, ecotparasite densities and grooming behavior-including licking and scratching-of wild-caught lesser bamboo bat (Tylonycteris pachypus) and greater bamboo bat (T. robustula) were analyzed. The results indicated that both the frequencies and durations of licking were higher than those of scratching in both bat species, though T. pachypus licked more but scratched less than T. robustula. There were no difference in the durations of licking and scratching between the two bat species, and the durations and frequencies of grooming behavior of the two bat species were irrelevant with ectoparasite densities. These findings suggest that the grooming behavior of T. pachypus and T. robustula might be modulated by both the central control (programmed grooming) model and the peripheral stimulation (stimulus driven) model.