Two adult cases of Ebstein's anomaly underwent Carpentier's procedure. In the first case longitudinal plication limited to free wall of atrialized ventricle was performed and postoperative course was uneventful. In the second case preoperative echocardiography showed apparently restricted movement of anterior leaflet of the tricuspid valve which was compatible with intraoperative findings. That is, inferior edge of anterior leaflet was partly adherent to ventricular wall and systolic bulging of leaflet was significantly impaired which was left untouched but should be repaired by additional procedure. Six days after operation the tricuspid valve replacement was required for persistent right heart failure due to residual tricuspid regurgitation. In the same case longitudinal plication of atrialized ventricle reported by Carpentier and colleagues resulted in excessively small annulus. Therefore we had to reduce the plication and did not perform following atrial plication to avoid direct injury to conduction system or disturbing coronary venous return. In conclusion exact preoperative evaluation of anterior leaflet of the tricuspid valve especially subvalvular anatomy is essential to Carpentier's procedure, as Carpentier and colleagues emphasized, and conservative longitudinal plication of the atrialized ventricle limited to free wall is favorable when excessively small annulus might be concerned.