目的　从已构建的人抗 - HBs Ag噬菌体抗体库中筛选出结合乙肝表面抗原 (HBs Ag)的特异的人噬菌体抗体 (Fab段 ) ,并进行基因序列分析 .方法　对噬菌体抗体库进行三轮“吸附 -洗脱 -扩增”的筛选 ,使特异性噬菌体抗体得到了富集 .EL ISA实验和 EL ISA竞争抑制实验鉴定出乙肝表面抗原的特异性抗体 ,同时对筛选出的克隆进行基因序列分析 .结果　得到与乙肝表面抗原特异结合的抗体 ,并通过基因序列分析证明为抗乙肝 HBs Ag的抗体 .结论　得到的抗乙肝 HB-s Ag的特异抗体为下一步表达纯化工作奠定了基础 OBJECTIVE: To screen out the specific human phage antibody (Fab fragment) that binds to hepatitis B surface antigen (HBsAg) from the constructed human anti-HBsAg phage antibody library and analyze the gene sequence.Methods The phage antibody library was subjected to three rounds of “ Absorption-Elution-Amplification ”, and the specific phage antibody was enriched.ELISA experiments and EL ISA competitive inhibition experiments identified specific antibodies against hepatitis B surface antigen, and the selected clones were sequenced .Results Antibody specific to hepatitis B surface antigen was obtained and proved to be anti-HBsAg antibody by gene sequence analysis.Conclusion The specific anti-HBsAg antibody could lay the foundation for the next purification of expression