Hydroxyurea is frequently used to treat myeloproliferative syndromes. Cutaneous lesions resembling those seen in dermatomyositis have rarely been reported in the course of treatment with hydroxyurea. We report six additional patients with this unusual adverse effect. All of the patients had a very typical and similar cutaneous eruption, with scaly, linear erythema on the dorsa of the hands. Leg ulceration occurred in two cases. Muscle involvement was never observed. One patient had unexplained lung disease. In all the others the disorder pursued a benign course, even when hydroxyurea was not withdrawn. Dermatomyositis-like lesions seem to be a not infrequent and characteristic adverse reaction to hydroxyurea. Investigations are not required, and the course is usually benign.