Colour Doppler flow imaging was used in this prospective, cross-sectional study to analyse renal haemodynamics in 50 cirrhotic patients and 15 healthy controls. Mean renal arterial resistive index (RI) was higher in cirrhotic patients than in healthy controls. Mean RI was also higher in cirrhotic patients with non-refractory ascites than in those without ascites, suggesting that the degree of renal vasoconstriction varies with the severity of ascites. A gradient of RI values across the main renal artery, interlobar artery and interlobular renal artery was retained in cirrhotic patients even in the decompensatory stage with non-refractory ascites but was not present in the decompensatory stage with refractory ascites. The disappearance of this gradient may be an important prognostic factor in the development of hepatorenal syndrome (HRS). An inverse correlation between creatinine clearance and interlobular arterial RI was shown for all cirrhotic patients suggesting that even patients with refractory ascites are in a prophase of HRS.