A 75-year-old man with mitral regurgitation (MR) and tricuspid regurgitation (TR) caused by Barlow 's disease was referred to our hospital. He had a history of persistent atrial fibrillation. Echocardiography showed severe MR with bi-leaflet billowing and functional TR. Cardiac index was 1.08 l/min/m2 without pulmonary hypertension. Through superior trans-septal approach, mitral valve was repaired by annuloplasty only using a partial ring so as not to induce systolic anterior movement. On the other hand, tricuspid valves showed severe billowing and prolapse, both of which were unexpected. Following tricuspid annuloplasty, we implanted two pairs of artificial chordae to both the anterior and posterior leaflet for leaflets' height reduction, thus TR was successfully controlled. There was no recurrence of significant MR and TR at three years follow-up.