We studied nectar-feeding behavior of 3 pteropodid bats under natural conditions. Cynopterus sphinx and Pteropus giganteus visited Ceiba pentandra trees throughout the night, whereas Rousettus leschenaulti visited only during early evening. Peak visits occurred at 2300 h for C. sphinx and 2000–2100 h for P. giganteus, coinciding with maximum nectar production and sugar concentration of floral resources. C. sphinx foraged at 6–10 m, R. leschenaulti at 10–18 m and P. giganteus at 15–20 m heights in the trees. Chemiluminescent-tagged C. sphinx foraged on nectar mostly in single trees until midnight and switched to 2–4 nearby trees later. We observed coats of pollen of C. pentandra on the abdomens, wings, and heads in 40% of C. sphinx captured in mist nets. Pollen loads on the abdomen were greater on males than on females. Our observations on R. leschenaulti and P. giganteus also showed adherence of pollen grains on their bodies. Presence of pollen grains on the bodies of these bats strongly suggests that they pollinate C. pentandra.