IL17A is a widely studied cytokine which plays an important role in autoimmune diseases as well as asthma. In this study, murine IL17a gene fragment was inserted into pET28a-Ag85A and it was expressed as a fusion protein named Ag85A-IL17A. Recombinant protein Ag85A-IL17A was expressed as an open reading frame of 1,287 bp, encoding a polypeptide of 429 amino acid residues with a predicted molecular mass of 50 kDa. It was expressed in Escherichia coli. BL21 and purified by metal affinity chromatography using a nickel-nitrilotriacetic acid column. Bioinformatics revealed that Ag85A-IL17A contained B cell epitopes of IL17A. Purified proteins Ag85A-IL17A and Ag85A were injected with adjuvants into mice then antibody responses in sera were measured by enzyme-linked immunosorbent assay and western blot assay. Experiments showed that purified protein Ag85-IL17A could bind to a standard IL17A antibody and could induce IL17A autoantibody in mice.