It is known that subaortic stenosis (SAS) occasionally progress after the repair of Co/A. And it may progress if the initial repair is incomplete. We successfully repaired a 6-year-old girl with recurrent SAS with aortic and mitral regurgitations and pulmonary hypertension (Pp/Ps=0.74) progressed after the initial repair for SAS. She had been operated at 4-year-old with transaortic resection of subaortic myocardium and the membrane. He SAS had progressed since the coarctectomy at 7 months of her age. At that procedure, right coronary cusp was lacerated and repaired. In may 1989, Konno operation with 21 St. Jude Medical aortic prosthesis and mitral valve replacement with 25 St. Jude Medical prosthesis were performed. Interventricular septum, aortic root and right ventricular outflow tract were reconstructed employing composite patch with preserved equine pericardium and Dacron velour. So mitral annulus was dilated because of the volume over loading due to aortic regurgitation, that complete repair was not able to do with mitral valvulo and annuloplasty. After the procedure severe cardiac and respiratory failure occurred and continued for over 10 days. And hemolytic anemia with homoglobiuria appeared. It continued for 14 days. In spite of those complications, the girl became well and goes to school with the administration of warfarin and dipyridamole. We recommend that Konno operation could be the first indication for the children with narrow aortic root when incomplete repair was made during the initial repair for subaortic stenosis.