A 49-year-old farmer had a history of recurrent knee effusion for 20 years. He did not report undergoing any diagnostic or therapeutic procedures apart from repeated aspirations of the joint fluid. After the isolation of Brucella melitensis from the joint fluid, computed tomography-guided bone biopsy was performed and histopathologic examination of the biopsy sample confirmed the diagnosis of chronic Brucella osteomyelitis. Arthroscopic synovectomy combined with antimicrobial therapy with doxycyclin, rifampicin, and ciprofloxacin for six months resulted in clinical recovery. This case indicates that brucellosis should be suspected in patients with non-specific and chronic osteoarticular symptoms, especially in endemic regions.