Objective To explore the therapeutic effect of bioprosthesis valve replacement under beating heart and mild hypothermia. Methods 242 cases of patients were underwent bioprosthesis valve replacement under beating heart and mild hypothermia,among them,15 cases was NYHA I, 190 Ⅱ - Ⅲ,37Ⅳ; 138 had a cardiothoracic ratio of,55 0. 5 - 0. 6, and 49≥0. 7; 186 were complicated with atrial fibrillation, 25 diabetes mellitus,and 32 infective endocarditis; 146 cases were performed with mitral valve replacement ( 36 were tricuspid annuloplasty ) ,22 aortic replacement surgery,49 mitral plus aortic replacement,and 25 re-valve replacement. Patients were followed up by telephone and outpatient clinic. Results 10 died during hospitalization,the mortality rate was 4% ( 10 /242) . 3 bradycardia,10 respiratory infection,4 low cardiac output syndrome,and 3 renal insufficiency were observed. Postoperative follow-up were receive in 190 cases, five died,175 cased were recorded with cardiac function recovered to grade Ⅰ -Ⅱ 175,and 10 to grade Ⅲ. Conclusion Bioprosthesis valve replacement under beating heart and mild hypothermia is showed with excellent therapeutic effect,safe,and feasible,especially for severe valvular disease and a huge heart,worthy of further promotion in clinical practice.