A 8-year old girl who complained with fever, vomiting and weakness was diagnosed as having left lung hydatid disease and was referred to our hospital for additional examination. In our hospital, a 7x5cm regular bordered mass, compliant with the appearance of hydatid cyst was detected in inferior segment of her left lung. Albendazole treatment was initiated as 10 mg/kg/day dose because her hydatid cyst antibody result was positive. The patient was operated after 15 days. Strongyloides stercoralis larvae were detected by the stool microscopic examination of the patient who developed diarrhea after the surgery, and the serum samples of her were positive for specific IgE to Ascaris and hydatid cyst. The patient was discharged from the hospital with the maintenance of antihelmintic treatment for 10 days and albendazole therapy for 6 months.