The early age of onset of acute rheumatic fever and a more rapid course wih frequent attacs of carditis leads to an overall earlier median age of valve replacement of Turkey. An important percantage of these patients are also children and adolescents. Smaller body size, altered hemodynamic patterns and accelerated metabolic rate differentiates this group of patients from the adults. Between January 1992 and January 1995 a total of 21 patients under the age of 16 were operated in our clinic. The youngest patient was 4 years old and the mean age of the patients were 11.38±3.63. Thirteen patients were operated for rheumatic valvular disease and 8 patients were operated for congenital valvular disease. The following valve replacements were performed; aortic valve replacement in 9 patients, mitral valve replacement in 3 patients.Valve replacements for congenital valvular lesions were 3 aortic valve replacements for aortic insufficiency with ventricular septal defect, 2 mitral valve replacements for congenital mitral insufficiency, 1 tricuspid valve replacements for Ebstein’s anomaly, 1 tricuspid valve replacements for Ebstein’s anomaly, 1 patient with mitral insufficiency with asymetric septal hypertrophy. Fifteen of the patients were in class III and six were in class IV preoperatively in regards to functional capacity. Bileaflet mechanical prostheses were used in all of the patiens except for the patient with Ebstein’s anomaly (15 Carbomedics, 8 Dura-medics). The following valve sizes were used: 16 mm aortic in 2 patients, 19 mm aortic in 7 patients, 21 mm aortic in 4 patients, 19 mm mitral in 1 patient, 23 mm mitral in 1 patient, 25 mm mitral in 3 patients, 27 mm mitral in 3 patients, 29 mm mitral in 1 patients, 27 mm mitral in 3 patients, 29 mm mitral in 1 patient, 31 mm mitral in 2 patients. 1 patient was lost with arrhythmia in the early postoperative period. Echocardiograms were performed in all of the patients in the postoperative period and 18 of the patient qere followed for a mean 14.3±4.8 months. None of the patients were lost during the late follow up period. This study has shown us that rapid valvular degeneration may cause left ventricular dysfunciton early in life. Valve replacemant in these patients with low profile bileaflet valves carries a low postoperative mortality even in very small children and the postoperative mid term follow up of these patients is satisfactory.