Objective To evaluate the diagnostic value of combined determination of DNA ploidy level and microRNA-21(miRNA-21)expression in ascites cells for hepatocellular carcinoma(HCC).Methods A total of 117 patients with ascites admitted to our hospital from January 1,2012 to January 1,2014 were enrolled.The patients with a confirmed diagnosis of HCC were assigned to experimental group(n= 48),and those without HCC to control group(n = 69).The risk factors for HCC were compared between the two groups.Logistic regression analysis was used to extract independent sensitive indicators.The receiver operating characteristic(ROC) curve for each indicator was drawn,and the area under the ROC curve(AUC) and Youden index(YI) were calculated.Results Univariate analysis revealed significant differences between the two groups in sex(male ratio),smoking history,positive rate of HBV,proportion of suspected positive cases based on upper abdominal CT,Karnofsky Performance Scale score,alanine aminotransferase,alpha-fetoprotein(AFP),abnormal prothrombin(APT),α-L-fucosidase,miRNA-21 expression in ascites cells,and the positive rate of DNA aneuploidy in ascites cells(all P < 0.05).Logistic regression analysis showed that smoking history,AFP,APT,miRNA-21 expression in ascites cells,and the positive rate of DNA aneuploidy in ascites cells were sensitive indicators for the diagnosis of HCC.The AUCs of miRNA-21 expression and positive rate of DNA aneuploidy were 0.742 and 0.801,respectively; the AUC and YI of combined use of smoking history,AFP,and APT were0.852 and 0.5992,respectively,while the AUC and YI increased to 0.869 and 0.6222,respectively,if including miRNA-21 expression and positive rate of DNA aneuploidy in combined determination.Conclusion DNA aneuploidy and miRNA-21 in ascites cells are independent risk factors for HCC.The two indicators have good diagnostic values when used separately,and they show increased diagnostic values when used in combination with other parameters(smoking history,AFP,and APT).Combined determination of these indicators has great clinical significance for the early diagnosis of HCC and is a good complement to the current HCC diagnosis system.