We report clinical and pathological features of enzootic nasal adenocarcinoma (ENA) in one sheep in Algeria. A one-year-old Ouled Djellal sheep from a large herd (similar to 1240 animals), located in Bordj Bou Arreridj, Algeria, was clinically diagnosed by the presence of persistent seromucous nasal discharge, head shaking, muzzle licking, dyspnoea, exophthalmia and frontal protrusion. The sheep was euthanized, and the necropsy was performed. Gross examination showed soft touch, pinkish-white tumour masses in the nasal cavities with distortion of the turbinates and of the medium septum. According to clinical and pathological findings, the tumour has been defined as a low grade mixed nasal adenocarcinoma, with the presence of tubular and papillary structures. This is, to our knowledge, the first report of ENA in Algeria known to be associated with enzootic nasal tumour virus (ENTV) infection. However, such association requires confirmation by direct and/or indirect viral investigation.