PURPOSE: We evaluated the results of arthroscopic intra-articular reduction and internal fixation of tibial plateau fractures without cortical window along with any additional bone grafts. MATERIALS AND METHODS: From March 2006 to March 2009, twelve patients with arthroscopic intra-articular reduction and internal fixation of tibial plateau fractures over 5 mm in depression and displacement on the articular surface in computed tomography (CT) were enrolled in this study. We reduced or removed the depressed fracture fragment using freer without making a cortical window. Then, we accomplished internal fixation by a cannulated screw. All cases have not received bone graft. Both the postoperative clinical and radiological results were evaluated by the Rasmussen system. RESULTS: The fractures were healed completely in an average of 9 (range from 7 to 12) weeks. According to Rasmussen classification, we obtained satisfactory clinical results as excellent in 8 cases, good in 3 cases, and fair in 1 case; and radiological results were excellent in 7 cases and good in 5 cases. CONCLUSION: We consider that arthroscopic intra-articular reduction and internal fixation of tibial plateau fractures without cortical window and any additional bone grafts is are a useful methods for attaining satisfactory results.