Brucellosis can affect all kinds of organs and can cause a wide range of clinical findings. The incidence of osteoarticular involvement in brucellosis has been reported to vary between 10-85% in various regions of the world. The most affected joints are knee, hip and ankle, respectively. However, it can affect all joints. Antibodies do not occur in 1-5% of cases with brucellosis and this is called seronegative brucellosis. It should be kept in mind that culture helps in definitive diagnosis for seronegative cases. In this case report, we aimed to emphasize that brucellosis should be considered in the differential diagnosis of peripheral arthritis, especially in older patients with risk factors in endemic areas even if serological tests were negative, and culture is essential to confirm the diagnosis.