Abstract: Objective To identify the structure and function of hyda tid disease diagnosticantigen P229 of Taenia saginata asitica,and to construct prokaryotic recombinant plasmids of the gene,to express and purify the recom binant prote in and conduct a preliminary immunoreacticity study.Methods By on line geneanalys is at bio infomatics websites,the gene from the Taenia saginata as iatica full-length cDNA plasmid libratory was identified.The coding region sequence and the characteristics of the deduced prote in were analyzed.The recom binant prote in was detected by SDS-PAGE after being induced with IPTG in Ecoli BL 21/DE3 and purified with NI-IDA affinity chrom atography.Its immunoreactivity was determined by Western blotting.Results The recom binant plasmid was successfully constructed.The recombinant prote in could react with Ta enia asiatica and Taenia rhynchus saginatus infected patient's serum.Conclusion The hydatid disease diagnostic an tigen P 229 of Taenia saginata asitica was cloned and expressed,and the purified protein was confirmed with immunogenicity.