Vitamin A is necessary to maintain the integrity and the differentiation of epithelia of the skin and adnexa. Evident deficiency of vitamin A in chronic diseases, malabsorption and liver affections may result in skin xerosis, follicular keratosis, and metaplasia of mucous membranes. The remarkable toxicity of vitamin A in high doses does not recommend its usage in dermatology. On the contrary the employ of retinoids, synthetic derivatives of vitamin A, brings to excellent results. These vitamin A compounds are much more effective, even if they show important side-effects. Etretinate and isotretinoin are widely used in psoriasis, keratinization disorders, and severe acne. Vitamin E functions in skin biology are not totally known. Vitamin E is used in the treatment of dermolytic recessive epidermolysis bullosa, with controversial results.