We here report on an unusual case of early renal transplant dysfunction due to renal vein compression. Graft function was initially good but oliguria and massive hematuria developed on the 3rd day after transplantation. Duplex sonography showed turbulent blood flow of the renal vein, and renal venography confirmed renal vein compression. Exploratory laparotomy was performed and diuresis was initiated just after nephropexy. In conclusion, renal vein compression is a rare complication but should be included in the possible causes of early renal transplant dysfunction since this can be simply diagnosed by duplex sonography and is easily remedied by nephropexy.