Anti-human AFP variant monoclonal antibody (AFP-R-LCA McAb) was labeled by 131I and injected intraperiton ealy. The 131I-AFP-R-LCA McAb was gathered in tumor of nude mice bearing human hepatocellular carcinoma (HCC). The tumor/liver radioactivity redio was 5.2, but normal mice IgG labeled by 131I-(131-mIgG) or free 131I was not gathered in tumor and distributed everywhere in average. The group of 131I-AFP-R-LCA McAb was positively visualized by gamma camea. The test showed that 131I-AFP-R-LCA McAb cured the nude mice bearing HCC. The tumor inhibition rate in 131I-AFP-R-LCA McAb group at the 4th week after treatment was significantly higher than those of the other groups (85%, 45%, 20%, 7% respectively, P < 0.05). The result showed that the AFP-R-LCA McAb have strong affinity and special combination to HCC cells and it can be recognized as a carrier for radioimmunodetection and radioimmunotherapy.