Abstract: We aim to discuss the growth and decline regularity of antibodies in the sheep inoculated with Brucella S2 by different approaches and to analyze fitting degree of the antibody results detected by different methods. We selected 44 Beijing native sheep under the same feeding conditions to perform single immunization. Twenty sheep were immunized by injection, with 5×108 CFU per sheep, the other twenty-four sheep were immunized by feeding, with 100 ×108 CFU per sheep. On the 3rd, 7th, 13th, 17th, 21st and 25th week, blood was sampled to separate serum. Then the 44 serum antibody samples were tested and analyzed with rose bengal plane test (RBPT), standard-tube agglutination test (SAT), micro-agglutination test (MAT) and enzyme linked immunosorbent assay (ELISA). The results showed that the serum of injection group maintained a certain antibody level on the 7th week and the antibody could be detected till the 25th week. However, the positive rate of feeding group was 0% on the 13th week. The Kappa values of RBPT, SAT and MAT compared with ELISA were 0.805, 0.760 and 0.899, respectively. The positive rate of antibodies in the injection group was higher than that in the feeding group, and the antibodies could be maintained for half a year. The consistency of the antibody test result was the highest between MAT and ELISA.