The evaluation of blood flow at the level of renal arteries by echo-Doppler may be useful in detecting a stenosis in patients affected by arterial hypertension. We studied 33 subjects with arterial hypertension using the most suitable scansions to visualize renal arteries. The measured parameters (R.I. and Vmax) resulted to be higher than normal range in 7 and 1 patients respectively. Then these patients underwent renal scintigraphy and arteriography; in 3 of them the presence of a stenosis of a renal artery was confirmed. Therefore the echo-Doppler study of renal arteries, even if has some shortcomings due to technic troubles, revealed to be a useful tool in the screening of hypertensive patients to support the other tools already used to this aim.