A sixty eight-year-old man was referred to our hospital for evaluation of hypertension and hypokalemia. His chief complaints were fatigability and weakness of the lower extremities. Atrophy of the right kidney was noted on computed tomography. The laboratory findings demonstrated massive proteinuria, markedly elevated plasma renin activity, hypokalemia, and renal insufficiency. Angiography showed total occlusion of the right renal artery. The patient was diagnosed as having nephrotic syndrome associated with renovascular hypertension. Treatment with candesartan, an angiotensin-II-receptor blocker (ARB), controlled both hypertension and proteinuria satisfactorily without worsening of his renal function. This is the first report on the effect of ARB on nephrotic syndrome associated with renovascular hypertension. Based on the results, ARB can be considered a promising agent for the treatment of patients with renovascular hypertension with massive proteinuria and renal insufficiency.