Objective To analyze the expression levels of γ-glutamyl transpeptidase( GGT) and alpha-fetoprotein( AFP) and their correlation in patients with hepatocellular carcinoma( HCC) and to evaluate their diagnostic values for HCC. Methods A total of 160 patients consisting of 84 cases of HCC and 76 cases of liver cirrhosis,who were examined in the department of clinical laboratory,Yulin Xingyuan hospital,from December 2011 to December 2014,were selected in this study. The difference and correlation of AFP and GGT expression levels in the two groups were analyzed. The diagnostic cut-off values were determined based on sensitivity,specificity,Youden's index,receiver operating characteristic( ROC) curve,and area under the ROC curve. Comparison between two groups was made by independent-samples t test or Mann-Whitney U test. The correlation between AFP and GGT was determined by Spearman rank correlation analysis. Results The AFP and GGT expression levels in the HCC group were significantly higher than those in the cirrhosis group( Z =-8. 993,P <0. 05; Z =-7. 647,P < 0. 05). The expression levels of AFP and GGT in both groups were positively correlated( rs= 0. 531,P < 0. 05;rs= 0. 416,P < 0. 05). There was also a positive correlation between the AFP and GGT expression levels for all the subjects( rs= 0. 701,P < 0. 05). The diagnostic accuracy of AFP and GGT for HCC was moderate. The maximum Youden's index was 0. 519 for AFP when its cut-off value was 100 ng / ml and the maximum Youden's index was up to 0. 494 for GGT when its cut-off value reached 150 U / L. A combination of AFP and GGT could increase the sensitivity and decrease the specificity in the diagnosis of HCC,but no significant change in the Youden's index for AFP was observed. Conclusion There is a significant positive correlation between the expression levels of GGT and AFP,but the combined measurement of AFP and GGT does not improve the accuracy of HCC diagnosis.