This study describes Crenosoma brasiliense (Nematoda, Metastrongyloidea), a new species parasitic in bronchi and bronchioles of Galictis cuja (Molina) (Carnivora, Mustelidae) from Brazil. This species differs from other 11 species of Crenosoma by having a cuticular projection at the distal end of the spicules, forming a prominent blade at the tip of the spicule, a vulval cuticular appendage with a triangular shape and prominent vulval lips. There are no previous records of species of Metastrongyloidea in G. cuja or species of Crenosoma in South America. Therefore, the new species represents the first host record and first geographical record of species of Crenosoma in South America.