Gemella infections, including bacteremia and infective endocarditis, are uncommon in humans. We report 2 cases of Gemella haemolysans (G. haemolysans) endocarditis during a 5-year period from an 811-bed university teaching hospital in the United Kingdom. One patient had prosthetic mitral and aortic valves, whereas the other patient had an aortic valve stenosis. In both patients, the presentation was subacute. The infection was complicated by vegetations on the posterior mitral leaflet in the first patient and early posterior paravalvular aortic root abscess formation in the second that required valve repair. The patients were treated with appropriate antibiotics for at least 4 weeks and discharged well. These patients were similar to those previously reported in 1) being male, 2) older, 3) with a prosthetic or abnormal heart valve, and 4) responding well to penicillin and gentamicin therapy. We also describe the epidemiological features of 18 patients with Gemella bacteremia.