A case of a pre-aortic left renal vein compression by the aorta is reported. The clinical presentation was characterized by the left flank pain varying with body body position. Renal venography was crucial for the diagnosis of this lesion. The left renal vein was successfully decompressed by ovarian vein-vena cava shunt surgery. The patient's left flank pain subsided after the surgery. This is the first reported case of a left renal vein compression syndrome by the aorta following the nephrotic syndrome.