Infected nonunion of the tibia was most serious complication in the tibial fracture and it have had many obstacles in treatment. Various treatment methods for infected nonunion have been performed to achieve bony union and restore bony defects after sequestrectomy. From Febrary 1991 to June 1993, the authors reviewed 12 cases who were treated for infected nonunion of the tibia with bone defect by the Ilizarov technique at National Medical Center to achieve union. to correct deformity, to eradicate infection, to reestablish limb length, and to eliminate bone defect. These infected nonunions were treated by on bloc resection of the diaphyseal shaft and internal bone transport. Final equalization of leg length inequality was achieved by external lengthening technique. Preoperative shortening was present in 1 of 12 cases and ranged from 1cm to 4cm (average,2.0cm). Bone defects size was ranged from 2cm to 7cm(average 4.5cm). Tibial corticotomies were performed at the proximal level in 8 cases and at the distal level in 4 cases. Regnerated new bone was ranged from fun to 9cm(average, 5.8cm). The average healing index was 2.54 months/cm. At an average 18 months follow up, according to Paley and Catagnis classification, bony results were excellent in five, good in six, poor in one and functional result were excellent in one, good in five, fair in five. poor in one. We concluded that the application of Ilizarov technique to resistant infected nonunion of the tibia with bone defect was very encouraging and useful method.