Abstract: Both TBa and TBb genes encoded tartary buckwheat allergenic protein’s two sununits, respectively. The genes were ligated into expression vector pET-28a and pET-32m for construct plasmids pET-28a-TBa and pET-32m-TBb. The two plasmids could be stably transformed and maintained in E.coli BL21(DE3) when both ampicilln and kanamycin were presented in the selective medium. After induction with IPTG, both TBa and TBb genes were coexpressed in E.coli, with their production as inclusion body. In the process of renaturation of coexpressed product, two subunits acted as molecular chaperones with each other, which promoted the refolding of protein TBa and TBb. ELISA indicated that the renatured protein had the improvement on the immunological activity and gained the activated protein. A new method for coexpression of proteins in E.coli containing two incompatible plasmids in which two different antibiotic resistant markers were included and inclusion body renaturation were also established.