A 43-year-old male renal allograft recipient was admitted to the hospital for annual check-up. He received a cadaveric renal transplant 2 years previously. On admission his physical examination did not show any abnormalities. Abdominal ultrasonography of the patient revealed a mass lesion in the upper pole of the right native kidney in 37 39 40mm in dimensions. The native kidneys were atrophic and had bilateral grade 3 increased echogenicity. A magnetic resonance imaging was performed which revealed a heterogeneous, complex cystic mass on the right native kidney (Figure 1). A right native nephrectomy was performed. The surgical specimen of the right kidney weighted 250 g, and measured 13 10 4 cm in dimensions. The cut surface of kidney revealed semisolid cystic lesions contained white-gray membranous structures. Histological examination revealed the lamellary membrane of the hydatid cyst (Figure 2). The serological tests for hydatid disease were negative. He was given 600mg/day of albendazole for 6 months. Patient was discharged in good condition after nephrectomy. Previously 10 different parasitic infections have been reported to infect renal transplant recipients [1]. According to our case report, hydatid disease is a new parasitic infection in a renal transplant recipient. An involvement of the kidney in hydatid disease is rare with an incidence of 2–3% concerning all cases [2,3].