Some urinary enzymes (NAG, AAP, lysozyme) considered to be sufficiently sensitive and reliable markers of renal damage were controlled in 20 patients with cirrhosis of the liver and in 20 healthy control subjects. The results, stated as mean +/- SD, showed a statistically very significant increase (p < 0.01) of NAG and lysozyme in cirrhotics. Furthermore, this increase could be at least in part related with the seriousness of clinical condition. On the basis of these results, we think the urinary dosage of NAG and lysozyme is, in the subjects with liver cirrhosis, a bloodless method to show an early renal damage.