Intracardiac correction of the combination of rare congenital heart lesion of anatomically corrected malposition of the great arteries, severe muscular as well as fibrous subaortic stenosis, and ventricular septal defects in the inflow and the trabecular septum in a 2 1/2 years old boy is reported. There was an additional large secundum atrial septal defect. The operation consisted of resection of the subaortic stenosis by a combined transatrial and transaortic approach, thereby regaining a wide outflow tract of the systemic ventricle. Both the ventricular and atrial septal defects were closed with Dacron patches. Reinvestigation 10 days after the operation revealed a residual pressure gradient across the outflow of the systemic ventricle of less than 10 mmHg. A secondary ventricular septal defect was detected in the anterior muscular septum at the same time and closed with a patch in a reintervention. At discharge from the hospital two weeks later the child was in excellent condition and had a stable sinus rhythm. The preoperative differential diagnosis of a double outlet right ventricle with L-malposition of the aorta as well as possible surgical approaches are discussed.