Background and study aim: Brucellosis is one of the most common zoonotic infections worldwide. Brucella organisms are able to survive and even multiply within mononuclear cells explaining the tendency of the disease to have a prolonged clinical course and relapse. The incidence of relapse in Brucellosis remains high; ranging from 5-30% of patients. The aim of this study is to evaluate possible risk factors of Brucellosis relapse. Patients and Methods: A retrospective study of 127 patients was conducted to evaluate risk factors of Brucellosis relapse. The diagnosis of relapse was based on recurrence of clinical picture within 3-6 months from treatment, increase agglutinating antibody titers and PCR. Different demographic, clinical, laboratory and serological parameters were studied based on the data gathered from the patients` electronic files. Results: Out of 127 patients, 21 (16.5%) patients were diagnosed as relapsers. No significant differences were found between relapsed and non-relapsed patients regarding age, sex, residence, clinical features, complications, lymphocytic count and serological titers. As regard treatment, regimens included Streptomycin and Doxycycline had a significant decrease in relapse occurrence. Conclusion: Anti-microbial regimen included Streptomycin and Doxycycline is the only preventive factor for Brucellosis relapse.