Background: The microvascular free fibula flap has become the gold standard for reconstruction of complex mandibular defects since its description by Hidalgo in 1989. Prior studies have demonstrated its safety and efficacy in the pediatric population. However, this reconstructive method is often used only as a last resort for correction of congenital mandibular hypoplasia, after failure of bone grafting and distraction osteogenesis. The authors describe our experience using this technique, facilitated by virtual planning and prefabricated cutting jigs, for children with severe congenital mandibular hypoplasia. Methods: All patients with mandibular reconstruction with a fibula flap in children with congenital mandibular hypoplasia between 2009 and 2014 by the senior authors were identified. Each patient underwent preoperative computed tomography scanning and virtual surgical planning to create custom cutting jigs for creation of the mandibular defect and fibular osteotomies. Preoperative, intraoperative, and postoperative medical records were examined in detail. Results: Five patients age 10 to 18 with congenital mandibular hypoplasia and Pruzansky Grade III mandibles underwent microvascular free fibula flap for mandibular reconstruction during this period. Flap success rate was 100%. All patients underwent subsequent revision procedures to improve symmetry or for hardware removal. The 4 patients in our series who required dental implants were able to have them placed into their mandibular reconstruction. Conclusions: Preoperative virtual planning and prefabricated cutting jigs allow for precise complex fibula reconstruction of the mandible in the pediatric population. Additionally, virtual planning facilitates concomitant orthognathic procedures in patients with hemifacial microsomia. Our early success in this patient population leads us to suggest that while the free fibula can be safely and successfully used after multiple prior surgical interventions in the same anatomic region, it can also be a powerful tool for primary correction of congenital mandibular hypoplasia.