The purpose of this study is to report the first case of parasitism by the giant kidney worm, Dioctophyme renale (Goeze, 1782), in the crab-eating fox, Cerdocyon thous (Linnaeus, 1766), in Brazil. A debilitated adult male fox was taken to the Screening Center for Wild Animals in Rio de Janero (CETAS/RJ) and eventually died of an unknown cause. During necropsy, a brownish-red nematode, 28.9 cm long, was found in the peritoneal cavity. The worm was identified as a male D. renale. This study reports the first case of dioctophymatosis in the crab-eating fox, enlarging the range of wild definitive host species infected by the giant kidney worm in the Neotropical region.