A three-year-old nephrotic girl is presented with vena cava superior syndrome. Angiography showed obliteration of the distal ends of both axillary veins and echocardiographic examination revealed a mobile mass in the right atrium. A thrombus originating from the vena cava superior with a stalk extending to the right atrium was surgically removed. To our knowledge, vena cava superior thrombosis in nephrotic syndrome has not been reported previously.