In 1983, Turner descrived a clinical entity in phenotype females characterized by sexual infantilism,congenital webbed neck and cubitus valgus. After then, the occurrence of renal anomalies in patients with Turner'ssyndrome has been recognized. Associated crossed fused renal ectopia is very rare. Primary retroperitonealteratoma is also rare and usually during childhood. The authors report a case of primary retroperitoneal teratomaand crossed fused renal ectopia with Tumer's syndrome(mosaic type). The clinical, pathological and radiographicalfindings are reviewed.