Parasitological and epidemiologlcal studies were done in a rural area on histoplasmosis, in Brasilia, D.F. where 14 persons had the disease. The clinicai, imunological and radiologic studies were reported in a previous paper. The isolation of H. capsulatum from soil of cave, víscera and blood from bats (Phyllostomus hastatus hastatus) were performed. The isolation of fungi from sentinel animais was negative as well the turn-over of intradermic tests of hystoplasmin carried out previously. Similar forms of T. gondii were observed in "printers" of viscera and subsequent isolation was made by inoculation of viscera macerate and blood, in young mice. Two ectoparasites were found in bats: Boophilus microplus and one diptera from the family Streblidae. In the acaro were found trypomastigotes; however this forms was not isolated. Nematodes (Histiostrongylus octacantus) and Cestodes from the Mathevotaenia genus were found in the digestive tract of Chyroptera. Two specimens from Cercomys cunicularis apereoide were captured near of cave but no parasitological studies were done. Intradermic test made in 826 peoples in the area gave 184 positives results (22,27%). The cave where the infection accurred is a calcareous formation Bambui type that seems to be from Silurian period based in tectonics aspects. The isolation of H. capsulatum from soil of Brazil, guanos, bats and viscera of rodents was done before. However this is the first time that the isolation of H. capsulatum was made from a cave-source of infection from viscera and from blood of bats. The intradermic tests with hystoplasmin shows the prevalence of hystoplasmosis infection in rural area of Federal District and we point out the possibility of the occurrence of another micro-epidemy and isolated case of hystoplasmosis disease.