Unilateral retinitis pigmentosa (URP) is a rare tapetoretinal dystrophy affecting only one eye. The François and Verriest criteria are necessary to make a correct diagnosis of URP: exclude all infective etiologies, check that the clinical signs of retinitis are present in the affected eye and ensure the total absence of any signs or symptoms of retinitis pigmentosa in the fellow eye. The standard electroretinogram and standard electro-oculogram are very useful for the correct diagnosis. Other pigmentary retinopathies simulating retinitis pigmentosa have to be excluded, such as previous retinal inflammatory diseases like syphilis, rubeola, other viral diseases and onchocerciasis. In this paper, 4 cases of URP are reported.