We report the case of a 52 year-old male in the chronic phase of chronic myeloid leukaemia, with Philadelphia chromosome due to t(9;22) in the karyotype. He was treated with courses of busulfan and hydroxyurea. Fourteen months after initial presentation, the patient developed fever, non-productive cough, maculonodular violaceous painful skin lesions and bilateral pulmonary infiltrates visible on a chest roentgen-ogram. Laboratory data, repeated bone marrow aspiration and biopsy and karyotype analysis showed findings similar to those of the initial diagnosis. A biopsy taken from one of the trunk lesions was consistent with Sweet’s syndrome. Oral methylprednisolone therapy was initiated at doses of 64 mg daily, and the skin lesions and fever were rapidly resolved. When we reduced the steroid dose, skin lesions and fever recurred. Two further courses of steroid therapy were given with similar results. Finally we treated him with naproxen (750 mg daily for 1 month) with a rapid and stable response. This drug should be considered as an alternative treatment for patients with Sweet’s syndrome not responding to corticosteroids or for immunocompromised hosts.