Smaller-size infants undergoing living-donor liver transplantation (LDLT) are at increased risks of vascular complications because of their smaller vascular structures in addition to vascular pedicles of insufficient length for reconstruction. Out of 585 child patients transplanted between June 1990 and March 2005, 64 (10%) weighing less than 6 kg underwent 65 LDLTs. Median age and weight were 6.9 months (range: 1-16 months) and 5 kg (range: 2.8-5.9 kg), respectively. Forty-five lateral segment, 12 monosegment, and 8 reduced monosegment grafts were adopted, and median graft-to-recipient weight ratio was 4.4% (range: 2.3-9.7). Outflow obstruction occurred in only 1 patient (1.5%). Portal vein complication occurred in 9 (14%) including 5 with portal vein thrombosis. Hepatic artery thrombosis (HAT) occurred in 5 (7.7%). Patient and graft survivals were 73% and 72% at 1 yr, and 69% and 68% at 5 yr after LDLT, respectively. Thirteen of 22 grafts (58%) lost during the follow-up period occurred within the first 3 months posttransplantation. Overall graft survival in patients with and without portal vein complication was 67% and 65%, respectively (P = 0.54). Overall graft survival in patients with and without HAT was 40% and 67%, respectively. HAT significantly affected graft survival (P = 0.04). In conclusion, our surgical technique for smaller-size recipients resulted in an acceptable rate of vascular complications. Overcoming early posttransplantation complications will further improve outcomes in infantile LDLT. Liver Transpl 12:1224–1232, 2006. © 2006 AASLD.