Objective To discuss the causes、prevention and treatment of complications of bone transport in the treatment of long bone defects of the lower extremities.Methods A retrospective analysis of 102 cases of long bone defects of the lower extremity treated with bone transport technique and followed up from January 2013 to December 2018was performed in 93 males and 9 females aged 12 to 71 years with an average of 34.6 years old. 13 cases of femur, 89 cases of tibia.The types, severity, treatment methods and results of complications occurred during or after treatment were analyzed statistically. Results 102 cases were followed up for 10-30 months with an average of 20 months. 81patients of the 102 patients followed, having a subgroup of 147 different types of complications (57 cases with 2 or more complications), 37 cases with delayed fracture healing, 33 cases with needle-tract infections, 9 cases of activity disorders, 24 cases of ankle movement disorders, 17 cases of skin depression, force line deviation in 8 cases, 5 cases of external compression carding skin, skin heat injury in 5 cases, 3 cases of recurrent infection, nerve injury in 2 cases, vascular injury 1 case, 1 case of fibula head dislocation, 1 case of broken needles, 1 case of osteotomy end-osteodystrophy. Anti-infection, replacing needle path, dressing, adjust the outer frame, strengthen functional exercise, re-operation and other treatment, can be effectively addressed, access to satisfactory results.Conclusion Application of bone transport in the treatment of long bone defects of the lower extremities Although there are some intraoperative and postoperative complications that can not be avoided, satisfactory and effective symptomatic treatment can still be obtained with satisfactory results and the morbidity and amputation rate are effectively reduced.