The Gram-negative bacterium Vibrio parahaemolyticus is a common pathogenic bacteria in aquatic products. Flagellin A,which is a specific protein in this strain,plays an important role during infection and induction of the host immune response. The polyclonal antibody against FlaA protein can be used as a probe in V. parahaemolyticus fast detection. In this study,the flaA gene from V. parahaemolyticus was amplified and the recombinant plasmid pET28a-flaA was constructed for production of FlaA. The FlaA was then expressed recombinantly with induction by isopropyl β-D-1-thiogalactopyranoside( IPTG). The soluble FlaA protein was purified by Ni-NTA affinity chromatography and the polyclonal antibody against FlaA was prepared by immunning rabbit. The final concentration of FlaA antibody was 24. 32 mg / mL with the titer of 1∶ 125,000. The ELISA estimation result showed that the FlaA polyclonal antibody had a sensibility of 1. 0 × 104CFU / mL. The FlaA polyclonal antibody showed no cross-reaction with 5 other kinds of pathogenic bacteria.