Brucella ovis is an infectious cause of ovine contagious epididymitis in sexually mature rams, resulting in orchid-epididymitis leading to major economic losses for the sheep industry worldwide .For serodetection of anti Brucella ovis antibodies among sexually mature rams with orchid-epididymitis by using commercial indirect enzyme-linked immunosorbent assays ( I-ELISA; IDEXX B. ovis Ab Test kit ; Idexx Montpellier, France).During the period from September 2017 to the September 2018, a 200 sera were collected from 42 commercial flocks in Mosul city, Iraq.Epididymides and testes were examined by palpation on farms. The results of the study revealed that, the seropositive animals for B. ovis infection was (12 \ 250) 4.8 % . In this study, the percentage of negative samples were higher than the positive samples .This is the first study of serodiagnosis of ovine contagious epididymitis in Mosul city, Iraq. The study provided important information for authorities to planning the control and eradication program.