Objective　Protein induced by vitamin Kabsence or antagonistⅡ（PIVKAⅡ），also called des－gamma－carboxy prothro mbin（DCP），is a sensitive marker for the diagnosis of hepatocellular carcinoma（HCC）inJapan and the United States since the sensitive kits were available（1998）．PIVKAⅡis not usedin clinicaldiagnosis in China so far．The aimofthis study was to assess the diagnostic value of PIVKAⅡin Chinesepatients with HCC．Methods　Seru mPIVKAⅡandα－fetoprotein（AFP）levels were determined in 60 patients with HCCand 30patients with cirrhosis not carrying HCC．Results　The mean serumconcentration of PIVKAⅡin HCCpatients（784．3±1364．1，x±s）was higherthan thatin cirrhosis patients（16．1±31．7）；this difference was highly significant（P＜0．0001）．When thecutofflevelof 40 mAU／ml was used as the level of discriminating HCCfromcirrhosis，51．7％of patients（31／60）with HCChad PIVKAⅡvalues above this level（sensitivity）．Only 4 patients with cirrhosis hadsuch high PIVKAⅡlevels．Thus，the specificity of this test was 86．7％（26／30）．Total accuracy was62．2％［（31＋26）／（60＋30）］．Seven of 19 small HCCs（36．84％）had PIVKAⅡvalues above the cutofflevel．Concentrations of AFPabove 20 ng／ml were observed in 34 of60 patients with HCC（56．7％）and in11 patients with cirrhosis（36．7％）．Eleven of 26 patients with HCC（46．2％）withoutincreased AFPhadconcentrations of PIVKAⅡgreater than 40 mAU／ml．No significant correlation was found between serumlevels of AFPand PIVKAⅡthat were measured in 60 HCCpatients（rs＝0．101，P＝0．247）．Combiningthe information fromPIVKAⅡand AFPshowed anincrease of approximately 21．6％over AFPand 26．7％over PIVKAⅡalone．For small HCCpatients，combining the information from PIVKAⅡand AFPshowedan increase of approximately 15．8％over AFPalone and 21．1％over PIVKAⅡalone．Conclusion　PIVKAⅡis a useful early diagnostic marker for HCCand may be more sensitive whencombined with AFPin Chinese patients．