AFP-L3 is one of AFP fractions which is synthesized by malignant cell and comprise special oligosaccharide.It is a new generation of tumor marker for HCC and yields useful information on HCC for clinical decision making. Reports at home or abroad have showed that if the ratio of AFP-L3 increased over 10%, the risk of catching HCC had increased highly, and non-malignant diseases hardly synthesize this AFP fraction(AFP-L3).AFP-L3 can be detected 9-12 months earlier and shows the remarkable precaution effect to HCC. AFP-L3 is the fucosylated variant of AFP produced specifically by HCC. AFP-L3 bears strong affinity to the sugar chain of Lens culinaris, a type of lentil. AFP-L3 had sensitivities and specificities ranging from 36% to 96% and 89% to 94%, respectively. AFP-L3 is less sensitive but more specific than AFP, and therefore cannot replace AFP. The value of AFP-L3 lies mainly in distinguishing HCC from other conditions when AFP is elevated.