Objective To analyze the causes of mechanical valve dysfunction and the reconstructive surgical procedure, and summarize the treatment experiences in perioperative period. Methods From October 1996 to October 2008, 12 276 patients underwent mechanical valve replacement in Fu Wai Hospital. Thirtytwo of them were reoperated because of mechanical valve dysfunction. There were 12 male and 20 female aged from 1661 years with an average age of 43.8 years. All the reoperations were performed under hypothermic cardiopulmonary bypass, including 16 mitral valve replacement, 8 aortic valve replacement, 3 aortic and mitral valve replacement, 3 tricuspid valve replacement, 2 disc rotation and 1 excision of an excessive knot. There were 13 emergency operation and 19 elective operation. Results The time of ventilator assistant respiration was 5.1-144.0 hours.The median time was 15 hours and tracheostomy was needed in 2 cases. Six patients died after reoperations, the mortality rate was 18.8%(6/32). Three died of low cardiac output syndrome, 2 died of multiple organ failure and 1 died of malignant arrhythmia. Three cases had complications. There were 1 infective endocarditis, 1 intractable hiccup and 1 incisional infection, respectively. They were all cured and discharged. Conclusion Prosthetic valve dysfunction is one of the serious complications after mechanical valve replacement. Early detection, early diagnosis and early reoperation are needed.