Objective To explore the safety and complications of repeated sternotomy after mitral valve repair and prevention strategies. Methods We retrospectively analyzed the clinical data of 88 consecutive patients of non-rheumatic mitral valve disease who underwent repeated sternotomy for failure of first-time mitral valve repair in our hospital from January 2009 through June 2015. There were 53 males and 35 females with a mean age of 36.1±17.5 years in the patients who underwent repeated sternotomy. Meanwhile 88 patients who underwent the first-time sternotomy for mitral valve repair simultaneously were randomly recruited as a control group, and there were 57 males and 31 females with a mean age of 39.9±12.6 years. The clinical outcomes were analyzed retrospectively and compared between the two groups. Results No major injury was observed in the patients who underwent repeated sternotomy. Eight patients (9.1%) in the repeated sternotomy group required femoral artery cannulation. Cardiopulmonary bypass (CPB) time was longer in the femoral artery cannulation group than that in the aortic cannulation group (155.5±59.0 minvs. 119.5±39.9 min,P=0.023). While there was no statistical difference in aortic cross-clamp time (P=0.786). Eight patients (9.1%) in the repeated sternotomy group used extra-pericardium approach. There was no significant difference in CPB time (P=0.255) or aortic cross-clamp time (P=0.360) between the patients who used extra-pericardium approach and those used routine approach. There was no statistical difference in post-operative complications between the patients who used different sternotomy strategies. Although CPB time (123.0±3.0 minvs. 95.4±37.1 min,P=0.000) or aortic cross-clamp time (79.0±36.3 minvs. 67.5±29.1 min,P=0.026) was longer in the repeated sternotmy group, the major outcomes were similar between the repeated sternotmy group and the first-time sternotmy group (P＞0.05). Conclusion Repeated sternotomy after mitral valve repair is relatively safe. With appropriate strategies, repeated sternotomy is not associated with increased risk of operative morbidity.