Abstract: A 79-year-old male presented with edematous erythema all over the body, cough, shortness of breath for 3 months. Repeated blood tests showed eosinophilic count >1.5×10⁹/L. Skin biopsy showed spongiotic perivascular inflammation with eosinophils and lymphocytes in the superficial dermis. Bronchoscopic biopsy showed eosinophilic infiltrates in tunica mucosa bronchiorum and alveolar septae. According to the clinical manifestation, laboratory examination and histopathological changes, the diagnosis of hypereosinophilic syndrome was made. The patient was treated with oral prednisolone at a dose of 75 mg once a day, and his cutaneous lesions and lung symptoms improved.