Ultrasound guidance may be a valuable adjunct for pediatric internal jugular vein catheterization. We previously reported a long-axis in plane technique, called the "three-step method", resulting in high success and a low complication rate by novice operators in adult patients. This is the first report of ultrasound-guided internal jugular vein catheterization (US-IJV) using the three-step method in pediatric patients. Fourteen junior residents underwent simulation training, and then participated in a clinical trial. They performed US-IJV in 14 pediatric patients with congenital heart disease before undergoing cardiac surgery under supervision of an experienced clinician. The overall success rate was 93 %, and all catheterizations were performed within two venipunctures. There were no complications associated with the procedure. The three-step method may facilitate pediatric US-IJV even by a novice operator during their first experience.