Brucella protein Omp19 was Expressed and purified, and its immunogenicity was further validated by Western blotting. An indirect enzyme-linked immunosorbent assay (iELISA) for detection of Brucella melitensis (B. melitensis ) was established using the purified recombinant protein Omp19 as coating antigen. Serum samples (n=90) from sheep were simultaneously tested by iELISA and standard serum agglutination test (SAT), and the data was analyzed by SPSS software. The results showed that compared with SAT the positive coincidence rate of iELISA was 95.12% and the negative coincidence rate was 67.35%, Kappa value was 0.607 7 . McNemar chisquare test showed that there was significant difference between the two methods (P<0.05). The total diagnosis coincidence rate reached 80%. The established iELISA could be used as an alternative method for serological diagnosis of brucellosis.