Rhodnius pallescens, reported to be the principal vector of Chagas' disease in central Panama, has been shown to feed on opossums, anteaters, sloths, rodents, birds and, rarely, lizards in sylvatic habitats in this country; however, the extent of its anthropophagic affinities in rural areas has never been determined. The host selections of 1,340 R. pallescens from domestic and peridomestic habitats of three Panamanian villages were determined by microcapillary precipitin tests. Slightly more than half of the triatomines collected in houses and nearby palm trees and bird nests had fed on humans. Opossums, which are important reservoirs of Trypanosoma cruzi in Panama, were the second most frequently selected host. The importance for the transmission of Chagas' disease to humans of the close relationship between the principal vector and reservoir in sylvatic and peridomestic environments and the anthropophagy of the former is discussed. Pigeons and chickens were the dominant bloodmeal sources of triatomines collected in their respective shelters. The roof rat, Rattus rattus, was the third most common mammalian host, and may represent an ancillary reservoir in the transmission of Chagas' disease in rural areas of Panama.