The registration of the fasciolosis was accomplished in Itaguai, Rio de Janeiro, Brazil. The verification of the presence was accomplished through coprologics and clinical exams and necropsias in bovine. The installation of the natural focus was verified through the encounter of the larval forms in Lymnaea columella captured in the farm. This registration, the first in the municipal district, is considered epidemiologically important due to the factors imposed by the socioeconomic conditions presented in the area in study.