Three members of one family with keratoderma Thost-Unna and histopathological picture of epidermolytic hyperkeratosis are reported. Several dermatoses with this abnormality of the keratinization are mentioned and the literature cases with keratoderma are reviewed. The treatment with oral aromatic retinoid though improved the hyperkeratosis, had to be discontinued because the vulnerability of the newly skin. Exhibited erosions with the consequent discomfort. The association of keratoderma with epidermolytic hyperkeratosis would be more frequently observed if the histopathological examination were performed in all cases.