We report a case of focal segmental glomerulosclerosis (FSGS) with chronic renal failure in a patient with unilateral renal artery stenosis. A 38-year-old woman presented with malignant hypertension, massive proteinuria and renal insufficiency. MR angiography showed proximal stenosis of the right renal artery and biopsy of the left kidney revealed focal segmental glomerulosclerosis. The patient responded favorably to the angiotensin Ⅱ receptor antagonist, as the blood pressure and urinary protein decreased. This case showed that FSGS is a pathophysiologic mechanism of renal injury in uncontrolled renovascular hypertension.