The prevalence of brucellosis was investigated in horses in Kars and Ardahan Districts of Turkey between 2008-2010. In order to achieve this, a total of 361 horse serum samples from 23 different villages were examined for Brucella antibodies by Rose Bengal Plate Test and Serum Agglutination Test. Of the 361 sera obtained from horses, 48 (13.29%) were determined positive by RBPT and 52 (14.40%) by SAT. The positive titers varied between 1/40 and 1/320 for brucellosis by SAT. Among the positive samples, the titers were 1/40 in 24, 1/80 in 6, 1/160 in 18 and 1/320 in 4 samples.