The intramedullary nailing is used widely and availably in the treatment of femoral shaft fracture. The conventional Kuntscher nailing has some problems such as angulation, shortening and rotational deformity in infraisthmal, comminuted shaft fractures, especially in distal one third shaft fracture. After development of the interlocking nails, for solving problems of the Kuntscher nail, the Brooker-Wills interlocking nail is used increasingly because of the simplicity of distal locking. The authors analyzed the results of 70 cases of femoral shaft fracture in 68 patients who were treated by means of Brooker-Wills nail at department of orthopedic surgery, Soonchunhyang university hospital. The results were as follows; 1) Among 70 cases in 68 patients, 61 patients (89.7%) were male and 7 patients (10.3%) were female. The average age was 32 years. 2) The most common cause of injury was traffic accident (59 patients, 89.7%). The most common fracture site was the middle ⅓ femoral shaft fracture, in 35 cases (50%). Most cases are comminuted fractures, which are classified using Winquist-Hansen classification. The type II is the most common (22 cases, 31.4%). 3) In the 66 cases, the union occured in 4.4 months in average. Delayed union in 3 cases, nonunion in 1 case were developed. The more comminuted, the longer the union time takes. 4) After union, complications including malunion and distal wing problems of Brooker-Wills nail revealed 14 cases and 4 cases respectively. The more distal and comminuted fractures were, the higher complication rate was. According to fixation type, the dynamic type revealed higher complication rate than the static type. 5) Both dynamic and static fixation were good results in the type I, II comminuted fractures of the proximal 1/3 and middle 1/3 shaft fractures. The type III, 1V comminuted fractures and the oblique fractures of the middle 1/3 revealed better results in the static type fixation. 6) The type I, II comminuted fractures of distal 1/3 were possible in the static fixation, but the type III, IV comminuted fractures and the far distal, supracondylar fractures were troublesome in the treatment by means of Brooker-Wills nailing.