The arterial switch operation (ASO) remains a challenging procedure, especially in cases with a complicated coronary anatomy. In recent years, the autologous flap extension technique has been used for coronary implantation in complicated ASOs. Operative techniques and indications are discussed in this report. From January 2006 to June 2011, ASO with the autologous flap extension technique for coronary implantation was used for 21 patients, including five cases involving transposition of the great arteries (TGA) with an intact ventricular septum, eight cases involving TGA with a ventriculoseptal defect, five cases of Taussig-Bing anomaly, and three cases involving corrected TGA. Age at operation varied between 3 and 314 days (median, 110 days). Body weight varied between 3.1 and 14 kg (median, 5.4 kg). Three patients underwent a two-stage operation. In all the patients, the main trunk of the right coronary artery or the dilated right ventricular conus branch originated from the left- or right-facing sinus and followed an abnormal course of anterior looping to the aorta. The operative techniques included a long coronary button excised from the aorta and a pedicle flap on the pulmonary artery (neoaorta) cut as a cuff extended to the button of the coronary artery with equal distance. The side edges of the flap and the button were sutured to each other, thus forming an extension tube that lengthened the coronary artery. No in-hospital operative mortality occurred. Delayed sternum closure occurred in five cases. The average mechanical ventilator time was 101.6 h. The average intensive care unit stay was 9.5 days. Follow-up evaluation after discharge was complete in 17 cases. Growth and development were improved in all patients. No ischemic electrocardiographic changes occurred. One patient underwent reoperation for supravalvular pulmonary stenosis 2 years later. The autologous flap extension technique for coronary implantation in complicated ASOs can decrease hospital mortality due to abnormal coronary arteries, especially for patients undergoing two-stage ASOs or patients whose main trunk of the right coronary artery or dilated right ventricular conus branch originates from the left- or right-facing sinus and follows an abnormal course of anterior looping to the aorta.