PURPOSE: To evaluate the results of bone transport using external fixator over an intramedullary nail for defects of long bone. MATERIALS AND METHODS: We treated 14 cases of bone defect after chronic osteomyelitis or trauma of tibia (12 cases) and femur (2 cases) using this method. The mean age of index procedure was 46.9 years, and all of them had follow-up study for a mean of 3 years. After the corticotomy and insertion of intramedullary nail, bone transport was done by external fixators. Then, the segment was moved and bone graft was done at docking site. RESULTS: The mean transported amount was 5.8 cm, and the external fixator was removed after 141 days. The mean external fixation index was 25.6 days/cm. Primary union of distraction and docking site was achieved in all, but one had failure in union of docking site. According to the Mekhail's functional criteria, there were 5 excellent, 6 good, and 3 fair results. Among 15 complications, there were 2 major complications with residual sequelae, and they were 1 recurred osteomyelitis and 1 flexion contracture of knee. CONCLUSION: Bone transport using external fixator over an intramedullary nail, can successfully solve defects of long bone. Since this method can remove external fixators earlier than the conventional method, it has fewer complications and makes patients to return to daily life earlier.