Objective To compare the postoperative outcomes of modified single-patch technique and one-and-a-half-patch technique for complete atrioventricular septal defect (CAVSD) with a large ventricular component (>1 cm). Methods We retrospectively reviewed clinical data of 79 CAVSD patients with a large ventricular component (>1 cm) in Shanghai Children's Medical Center from January 2005 through January 2016. There were 37 males, 42 females with a median age of 8 months (range, 1.5 months to 10.2 years). Among the patients, 45 patients (20 males, 25 females) with a median age of 6 months(range, 1.5 months to 10.2 years) received modified single patch technique and 34 patients (17 males, 17 females) with a median age of 5.3 months (range, 2.5 months to 8.3 years) underwent one-and-a-half-patch (1.5-patch) technique. All the patients complicated with complex malformation such as double outlet of right ventricular, single ventricle, and transposition of great arteries were excluded. Results The mortality and reoperation rate in modified single-patch group were higher than those of the one-and-a-half-patch group. There were 2 postoperative early deaths in the modified single-patch group (4.4%). Among them, one patient died of postoperative valvular regurgitation and heart pump failure. The other one died of respiratory failure caused by severe pneumonia. There were 3 reoperations. Two patients performed valve plastic surgery because of valve regurgitation and one patient because of residual ventricular septal defect. There was no death and reoperation in the one-and-a-half-patch technique group. No left ventricular outflow tract obstruction and atrioventricular block in both groups were developed. Conclusion The 1.5-patch technique is an attractive clinical option in CAVSD patients with a large ventricular component.