Twenty segmental fractures of the long bone were treated at National Medical Center, Department of Orthopaedic Surgery during the period from Jan. 1987 to Dec. 1990. We classified the segmental fracture as AO classification and compared each end result according to the treatment methods and fracture type. Ten fracture (50%) were open and ten were closed. Fifteen cases (75%) were car accident. Nine cases (45%) were C2.2 in AO fracture classification. In nine cases, we performed intramedullary nailling, six cases open reduction & internal fixation with plate, five cases cast immobilization. The average bone healing time were in order of C2.1 C2.2 C2.3. In C2.1 fracture, there was little difference of union time between intramedullary nailling and open reduction & internal fixation with plate. But it was longer in open reduction & internal fixation with plate in cases of C2.2 and C2.3. There were some complications. Three cases were delayed union, one case nonunion, one case joint stiffness and two cases bone infection in open reduction & internal fixation with plate. In intramedullary nailing, one case had a delayed union, one case joint stiffness, one case angular deformity. In cast immobilization, one case delayed union, one case nonunion, three cases joint stiffness. In C2.2 fracture, two cases had a delayed union, two joint stiffness, three bone infection and in C2.3 fracture, two had a delayed union, two nonunion, three joint stiffness and angular deformity. In conclusion, intramedullary nailing is the treatment of choice in case of C2.1, C2.2 & C2.3 But in C2.1 fracture, open reduction and internal fixation with plate is another choice of treatment.