Brucella endocarditis is a zoonosis transmitted by contaminated dairy products. Endocarditis is a rare complication of brucellosis and mainly the aortic valve is infected. We present the case of a female patient with prosthetic mitral valve endocarditis associated with QT prolongation and torsades de pointes. Transesophageal echocardiography revealed vegetation on both anterior and posterior mitral annulus. She was seropositive with Brucella agglutination titers of up to 1/320. The QT interval was markedly prolonged upon admission (QTc 530 ms). She experienced torsades de pointes several times. She underwent reoperation under an appropriate antibiotic regimen. She continued on triple antibiotic therapy for 12 months. She is now well and free of symptoms.