Dioctophymosis is the disease caused by Dioctophyma renale, a large nematode, popularly known as giant kidney worm, and whose definitive hosts are the domestic dog and many wild mammal species. There are some reports of maned wolf parasitism by D. renale, however, in most cases the reports are restricted to the finding of the parasite during necropsy, without clinical assessment. The present report aimed to describe the clinical-therapeutic, ultrasonographic and pathological aspects of D. renale parasitism in a free-ranging maned wolf, emphasizing the treatment with an association of doramectin, praziquantel, pyrantel pamoate, and febantel that resulted in complete elimination of the parasite.