This is a report on the clinical history and pathological lesions of a dog suffering from disseminated protothecosis due to Prototheca zopfii. Clinically, the dog was presented with bilateral conjunctivitis followed by blindness, deafness and posterior paresis. Pathological lesions were most severe in the eyes and consisted of subacute panophthalmitis with secondary posterior subcapsular cataract, posterior synechia, retinal detachment and microscopic evidence of glaucoma. The kidney, liver, brain, spleen and lungs were also affected. This is believed to be the first published account of protothecosis in mammals other than man in Africa. A review of the literature is included.