We report a case of nutcracker syndrome diagnosed with 3-dimensional computed tomography angiography (3-D CTA). Nutcracker syndrome had been confirmed by conventional venography until recent years. Nowadays, with the development of imaging techniques, color Doppler sonogram and 3-D CTA are replacing venography for the diagnosis of nutcracker syndrome. The patient, a 20-year-old male, had abrupt gross hematuria and left abdominal pain 6 months previously and intermittent microscopic hematuria thereafter. Including renal biopsy, the results of conventional hematuria study showed no abnormalities. 3-D CTA showed left renal vein compression between the abdominal aorta and superior mesenteric artery and collateral veins. The angle and distance between the superior mesenteric artery and aorta at the level of the left renal vein were 35^o and 3.0 mm, respectively. We diagnosed nutcracker syndrome and later confirmed the diagnosis with venography.