Abstract：Objective To explore the clinical values of alpha-fetoprotein-L3（AFP-L3) in diagnosis of primary liver cancer．Methods The serum samples of 137 patients with elevated AFP level (>10ng/mL）were detected by chemiluminescence immunoassay for AFP and centrifugal column method was used for AFP-L3 measurement．The proportion of AFP-L3/A FP（％）was calculated in the following analyses．Results T serum level of AFP-L3 in primary liver cancer group, liver cirrhosis group, chronic hepatitis B group, and control group were 17.63±5.78%, 8.24±2.49%, 7.12± 2.01% and 5.49±1.78%，respectively．The positive rate of AFP-L3 was significant higher in primary liver cancer group than other groups（P<0.01）．Area under the ROC curves of AFP-L3 was 0.894．Conclusion  AFP-L3could be used as biomarkers in the diagnosis of primary liver cancer, and may also has a clinical value in the auxiliary diagnosis and differential diagnosis．