During an outbreak of mucocutaneous leishmaniasis in Praia Vermelha, Ilha Grande (Great Island) in the county of Angra dos Reis, State of Rio de Janeiro, 4.192 species of Phlebotomus were collected in domestic and wild environment with the use of animal baits and other natural shelters from January 1976 to April 1977. In a total of 11 species collected, 2.493 samples of Lutzomyia intermedia, 1.594 of Lutzomyia migonei and 105 samples of other species were found. The Lutzomyia intermedia presented a higher density in human dwellings, while the Lutzomyia migonei presented better results with animal baits and chicken-coops. The sinantropism and high density found in the houses incriminate the species L. intermedia and L. migonei as the probable vectors of Mucocutaneous Leishmaniasis in Ilha Grande.