Objective To compare the clinical outcomes and safety of minimally invasive and routine mitral valve repair or replacement for patients with single mitral valve disease. Methods We retrospectively analyzed the clinical data of 67 patients with single mitral valve disease （without aortic valve and tricuspid valve lesion or other heart diseases including atrial septal defect） who underwent mitral valve repair or replacement in the First Affiliated Hospital of China Medical University between January and July 2011. The patients were divided into two groups according to different surgical approaches：the minimally invasive surgery group （n=29，8 males and 21 females，age 51.4±9.4 years） underwent minimally invasive mitral valve repair or replacement via right mini-thoractomy；and the routine surgery group （n=38，11 males and 27 females，age 53.6±11.9 years） underwent mitral valve repair or replacement via middle sternotomy. In the minimally invasive surgery group，9 patients underwent mitral valve repair while the other 20 patients underwent mitral valve replacement. And no patient underwent transition to routine operation. In the routine surgery group，15 patients underwent mitral valve repair and 23 patients underwent mitral valve replacement. Clinical outcomes and safety of the operations were compared between the two groups. Results There was no statistical difference in operation time between the two groups （207.9±18.1 min versus 198.4±27.5 min，P=0.076）. The amount of postoperative drainage （126.7±34.5 ml versus 435.6±87.2 ml，P=0.000） and blood transfusion （red blood cell 1.4±0.8 U versus 2.3±1.1 U，P=0.000；blood plasma 164.3±50.4 ml versus 405.6±68.9 ml，P=0.000） of the minimally invasive surgery group were significantly lower than those of the routine surgery group. The cardiopulmonary bypass time （81.7±23.9 min versus 58.7±13.6 min，P=0.000） and aortic-clamping time （51.6±12.7 min versus 38.4±11.7 min，P=0.000） of the minimally invasive surgery group were significantly longer than those of the routine surgery group. The length of ICU stay （22.5±3.6 h versus 31.7±8.5 h，P=0.000），mechanical ventilation （7.4±3.2 h versus 11.2±5.1 h，P=0.000） and postoperative hospitalization （7.1±1.6 d versus 13.5±2.4 d，P=0.000） of the minimally invasive surgery group were significantly shorter than those of the routine surgery group. There was no statistical difference in postoperative complications between the two groups. Minimally invasive surgery group patients were followed up for 5.3±2.4 months with a follow-up rate of 72.4%（21/29）. Routine surgery group patients were followed up for 5.5±3.8 months with a follow-up rate of 71.0%（27/38）. There was no significant complication during follow-up in both two groups. Conclusion Minimally invasive mitral valve operation via right mini-thoracotomy is effective and safe with a good cosmetic result. Compared with routine operation，patients undergoing minimally invasive operation recover better and faster.