Abstract: The aim of this study was to establish an indirect ELISA for detection of antibodies against avian infectious bronchitis (IB). The published amino acid sequences of S1 gene of avian Infectious bronchitis virus (IBV) strain ZY3 were analyzed by bioinformatics software, and four dominant epitopes named as F1, F2, F3 and F4 were selected and ligated together as a chimeric gene F. Bioinformatic analysis showed that this protein if highly antigenic and flexible. Then the chimeric gene was then inserted into expression vector pET-32a（+）for the expression of target gene and a 42 kD recombinant protein was obtained. The result of westernblot showed that the chimeric protein could react specifically with anti-IBV positive serum. An indirect ELISA was then developed using purified protein as coating antigen.175 sera samples were examined by this ELISA and commercial kit, the results showed that the positive coincidence rate could reached 90.2%, negative coincidence rate could reached 85.7%, and the total coincidence rate reached 89.7%. The results indicated that the indirect ELISA was sensitive and specific, and no cross-reaction with positive sera of other chicken diseases. The indirect ELISA for detection of chicken antibodies against Infectious bronchitis were successfully developed.