Abstract: Objective: To construct expression vector of the metalloproteinase domain of human tumor necrosis factor-α converting enzyme(TACEmp) and express its protein in E.coli.Methods: RT-PCR and sequencing were used to clone and confirm the TACEmp gene.The fusion expression vector was constructed with the prokaryotic expression vector including disulfide isomerase dsbA gene and the TACEmp,named pET-DsbA^mut-TACEmp,and transformed into E.coli.BL21.After induced by IPTG,expression product was analyzed by SDS-PAGE.Results: TACEmp was cloned by RT-PCR.The recombinant vector pET-DsbA^mut-TACEmp was constructed.The fusion protein was expressed at high level in E.coli.Conclusions: The TACEmp was expressed at high level in prokaryotic expression system by using fusion protein technology.The expression of TACEmp protein may be useful for the study of biological functions of TACEmp and it's biotherapy in TACEmp related diseases.