Fractures of the tibial shaft are the most common among the long bone fractures, and have much difficulty in treatment due to their enumerous complications. Flexible Ender nailing is considered to be a valuable method in treating tibial shaft fracture because of their relative ease of nailing, allowing early weight bearing and decreased complications. Twenty-one patients having tibial shaft fractures, were carried out Ender nailing, at Department of Orthopaedic Surgery, Yonsei University College of Medicine from January 1987 to December 1989. The results are follows;l. Among 21 patients, 17 cases were male and 4 cases were female. The average age was 31.9 years and the most common cause of injury was traffic accident. 2. Ten cases out of 21 were closed fractures and the remaining 11 were open. The comminuted fractures were 18, and the most common fracture site was middle one-third. 3. Average interval from injury to operation was 12.8 days and in 13 cases show the associated injuries. 4. The mean duration of the bone union was 22.4 weeks. 5. Ten complications were 6 cases of delayed union, and 2 cases of nonunion, and noted such as superficial wound infection, joint stiffness, and angulation. Through the results Ender nailing is the simple internal fixation procedure that promote bone union because of allowing early weight bearing without periosteal stripping in the tibial shaft fractures, especially, severe comminuted and segmental fractures.