The rationale for proximal tibial osteotomy is to correct the abnormal loading stresses on the knee that are caused by an abnormal tibiofemoral axis in the coronal plane. Aithough there are many methods of fixation including cast, staple and external fixation, Coventry staple has been used widely. But Coventry staple has some disadvantages such as inadequate fixation, long term cast immobilization and rehabilitation. The purpose of this study is to demonstrate the superior performance of Miniplate staple which was designed by authors(Johnson & Johnson Orthopaedics, New Milton, UK) over the conventional Coventry staple. We have analyzed the clinical results including postoperative rehabilitation course of 3I cases who had proximal tibial osteotomy fixed with Miniplate staple. Preoperative diagnosis was osteoarthritis(OA) in 24 cases(77.4%) and physiologic genu varum in 7 cases(22.6%). 1. Hospital for Special Surgery knee score was average 72.2 points preoperatively, 90.1 points postoperatively in osteoarthritis and average 94.1 points preoperatively, 99.7 points postoperativeiy in physiologic genu varum. 2. The average tibiofemoral angle was varus 5.8 degrees preoperatively and valgus 8.7 degrees postoperati vely. 3. The active ROM exercise started at 5.3 days, standing at 13.3 days, crutches ambulation at 20.2 days and ambulation without crutches at 46.3 days after operation. In conclusion, more rigid fixation and rapid mobilization was possible with newly designed Miniplate staple in proximal tibial osteotomy.