Hypereosinophilic syndrome is a spectrum of disorders characterized by marked eosinophilic leukocytosis without identifiable cause or organ dysfunction. We report 37 years old man applied with nonproductive cough and itchy skin eruptions for one year. At the physical examination there were nodular erythematous lesions on his upper extremity. We didn`t find any reason which can explain the eosinophily like allergic disease, mycotic infections, parasitic infections, malignancy and collagen tissue diseases with his anamnesis, clinical findings and laboratory tests. He was diagnosed as hypereosinopyhilic syndrome, and treated with hydroxiure. After treatment his skin lesions, leukocytosis and eosinophily were regressed.