The frequency of the patellar fracture is increasing because of increasing traffic accident & sports activities and its treatment is considered very important because the involvement of the articular surface occurs in most of it. The authors experienced 54 cases of patellar fracture from January, 1979 to October, 1980 at the Department of Orthopedic surgery, Capital Armed Forces General Hospital and the results were as follows. 1. The most fractures were encountered in man of 3rd. decade. 2. Thirty-eight (70.4%) fracture were induced by direct blow and the remainders were induced by indirect violence. 3. The most fractures were stellate, communited fractures (44.4%) and transverse fractures (37%) which mostly occured at the middle portion. 4. The most fractures were treated by conservative method, circumferential wiring, tension band technique and patellectomy, and the result of the tension band technique was superior to other operative methods (shorter immobilization time, rehabilitation time, and wide range of motion of the knee joint and longer midthigh circumference). 5. The rehabilitation period was shorter in the group of immobilization in 10° flexion of knee with cylinder cast than in the group of immobilization in full extension of knee. 6. Skin lacerations, femoral fractures, and tibial fractures were associated injuries, and the superficial infections and peroneal nerve palsy were complicated.