Objective To evaluate the relation of serum cystatin C (CysC) and urotensin II (uII) levels with presence of hepatorenal syndrome in patients with decompensated liver cirrhosis to determine the diagnostic potential for these serum markers in order to facilitate early detection of hepatorenal syndrome at subclinical stages.Methods A total of 50 patients with decompensated liver cirrhosis were recruited for study and divided into three groups according to creatinine elimination rate (Ccr) : simple liver cirrhosis, ≥80 ml/min (n=22) ;subclinical hepatorenal syndrome, 40≤Ccr<80 ml/min (n=19) ;and hepatorenal syndrome, ≤40 ml/min (n=9) .Fifteen healthy individuals were recruited for use as controls.Fasting blood samples were collected from all cases and controls for measurements of alanine aminotransferase (ALT) , aspartate aminotransferase (AST) , total bile acid (TBA) , albumin (Alb) , serum creatinine (Scr) , CysC, and uII.For normally distributed data, single-factor analysis was carried out by One-Way ANOVA and pairwise comparisons were carried out by the Student′s t-test;for non-normally distributed data, the Kruskall-Wallis H test and Mann-Whitney U test were used, respectively.Correlation analysis was carried out with the Spearman′s rank correlation coefficient.Diagnostic accuracy was assessed by generating a receiver operating characteristic (ROC) curve and using the area under the curve (AUC) to select the optimal threshold for diagnosing subclinical hepatorenal syndrome and hepatorenal syndrome in patients with decompensated liver cirrhosis.Results Compared to the healthy controls, the cirrhosis cases had significantly higher levels of ALT, AST, TBA, ALB, Scr, CysC, and uII (all P<0.05) .However, among the cirrhotic patients, those with subclinical hepatorenal syndrome and hepatorenal syndrome had slightly, but significantly, higher levels of CysC and uII than the patients with simple cirrhosis (both P<0.05) .For subclinical hepatorenal syndrome, the AUCs of CysC and uII were 0.91 and 0.867 and the optimal thresholds were 1.40 mg/L and 299.06 pg/ml respectively.For hepatorenal syndrome, the AUCs of CysC and uII were 0.942 and 0.901 and the optimal thresholds were 2.22 mg/L and 321 pg/ml respectively.Conclusion Enhanced levels of serum CysC and uII can reflect hepatorenal damage in patients with decompensated liver cirrhosis, even when serum creatinine levels are within normal range, suggesting that these two serum markers may have diagnostic value for detecting subclinical hepatorenal syndrome and hepatorenal syndrome at early stages in this patient population.