Brucellosis is a Zoonosis, recognized worldwide as a serious public health hazard and economically significant disease. The etiologic agent of this disease is a bacterial species of the genus Brucella that causes undulant fever, sterility and other systemic illnesses in human. Thus, the aim of this study was to undertake seroepidemiological study of brucellosis on occupationally exposed persons in Addis Ababa abattoirs enterprise and different dairy farms. Three hundred thirty six human individuals were screened using Rose Bengal Plate Test (RBPT) and the sera were further subjected to 2- Mercapto Ethanol Test (2-MET). Simultaneously, survey was conducted in farms and slaughterhouse to investigate epidemiological factors. An overall seroprevalence rate of 4.8% (16/336) was determined by taking RBPT+/2MET+ as confirmatory test (P < 0.05). Some of the risk factors contributing to the occurrence of the disease include occupation, gender, and unsafe handling of infected materials. Raw milk and meat consumption, lack of awareness and use of detergents were also found as important factors. The seroprevalence of brucellosis is expected to be more in other areas of the Region, where there is high human-animal contact and high number of cattle population with a respective traditional system of animal rearing.