The aim of this work, synthesized from personal case reports and a review of literature is to describe cutaneous complications of radiation therapy (except radiation-induced cancers): known and frequent such as radiation dermatitis or less frequent, beginning or strictly limited on irradiated skin areas: acne, infectious diseases, dyskeratosis, Grover's disease, sub-cutaneous pustulosis, cutaneous lichen, morphea, autoimmune bullous dermatosis, subacute cutaneous lupus erythematosus. Furthermore, we try to precise the physiopathogenic mechanisms of these dermatosis and we want to draw the attention on these dermatoses which sometimes need a multidisciplinary approach.