The purpose of our study was to address the long-term outcome of angioplasty and stent placement for hepatic venous outflow obstruction following pediatric liver transplantation. From October 1999 to December 2011, 20 stenotic lesions were confirmed to constitute hepatic venous outflow obstruction in 18 pediatric patients (13 boys, 5 girls) among 152 pediatric patients following liver transplantation and were managed with endovascular intervention. Stent placement was favored over additional angioplasty in patients of preadolescent or adolescent age (>8 years old), after 1 or 2 sessions of balloon angioplasty. The primary patency and assisted primary patency were estimated using the Kaplan-Meier method. A total of 32 procedures (24 balloon angioplasties, 8 stent placements) were conducted. The technical success rate was 90.6% (29/32). Clinical success was achieved in 15 of 18 patients (clinical success rate of 83.3%). Major complications did not occur in our study. Median follow-up was 91.5 months (interquartile range, 54.7-137.3 months) for the 18 patients. The 1-year, 3-year, 5-year, and 10-year primary patencies of the 20 treated lesions were 63.5%, 57.8%, 57.8%, and 57.8%, respectively. The 1-year, 3-year, 5-year, and 10-year assisted-primary patencies of the lesions were 100%, 100%, 100%, and 100%, respectively. Of the 6 patients of preadolescent or adolescent age, 5 patients underwent stent placement procedures, and the stents were patent during the follow-up period of 57.3-162.5 months (median, 72.7 months). In conclusion, endovascular intervention is very effective in hepatic venous outflow obstruction following pediatric liver transplantation. In addition, early stent placement in patients of preadolescent or adolescent age can provide a safe and favorable long-term outcome.