Mitral and aortic valve replacement with tricuspid annuloplasty was undertaken in 5 patients out of 38 valvular surgery between the period from Jan. 1977 to May 1979 in the Dept. of Thoracic and Cardiovascular Surgery in Korea University Hospital. All were male patients with age ranging from 18 to 42 years, and preoperative evaluation revealed one case in Class IV, and four cases in Class III according to the classification of NYHA. Preoperative diagnosis was confirmed by routine cardiac study including retrograde aorto- and left ventriculography, and there were two cases with MSi+ASi+Ti, two cases with MSi+Ai+Ti, and one case with Mi+Ai+Ti. Double valve replacement was performed under the hypothermic cardiopulmonary bypass with total pump time of 247 min. in average ranging from 206 min. to 268 min. During aortic valve replacement, left coronary perfusion was done in the first two cases, and cardiac arrest with cardioplegic solution proposed by Bretschneider was applied in the remained three cases. Starr-Edwards, Bjork-Shiley prosthetic valves and Carpentier-Edwards tissue valve were replaced in the aortic area, and Carpentier-Edwards and Angell-Shiley tissue valves were replaced in the mitral area with each individual combination [three prosthetic and two tissue valves in the aortic, and five tissue valves in the mitral area respectively]. Postoperative recovery was uneventful in all cases except one case with hemopericardium, which was managed with pericardiectomy on the postoperative 10th day in good result. Follow-up after double valve replacement of the all five cases for the period from 6 months to 33 months revealed satisfactory adaptation in social activity and occupation with cardiac function of Class I according to the classification of NYHA In all five cases.[KTCS 1979;4:355-360]