Twenty-one Sotalia guianensis (van Bénéden, 1864) and one Steno bredanensis (Lesson, 1828) stranded on Brazilian coast were necropsied. Two species of Nasitrema (Trematoda: Brachycladiidae) Ozaki, 1935, were identified in the respiratory tract of the dolphins. Nasitrema atenuatta (Neiland, Rice and Holden, 1970) was found in S. guianensis (prevalence 28.7%, mean intensity 4.66 and mean abundance 1.33) and S. bredanensis (mean intensity and mean abundance six helminths). Nasitrema globicephalae (Neiland, Rice and Holden, 1970) was only found in S. bredanensis, with an infection intensity of 14 helminths. Nasitrema atenuatta and N. globicephalae are reported for the first time in South Atlantic.