PURPOSE: We wanted to evaluate the clinical and radiographic results of robotic-assisted implantation of TKAs with a minimum follow-up of three years. MATERIALS AND METHODS: 50 TKAs using ROBODOC(R) (Integrated Surgical Systems, Sacramento, CA, USA) were included in this study. We assessed the radiographic measurements with regard to the change of the mechanical axis and the inclination of the femoral and tibial components. The clinical results were evaluated with using the range of motion (ROM), the Hospital for Special Surgery (HSS) scores and the Western Ontario and McMaster University (WOMAC) scores. RESULTS: The angle formed by the mechanical axis of the femur and tibia was corrected from 6.57degrees varus to 0.49degrees valgus. The mean coronal inclination of the femoral and tibial components was 89.52degrees and 90.12degrees, respectively, and the mean sagittal inclination of the femoral and tibial components was 1.06degrees and 85.56degrees, respectively. There were 45 excellent and 5 acceptable results for the femoral component, and 38 excellent and 11 acceptable results for the tibial components. On the clinical assessment, the ROM improved from 124.9degrees to 128.4degrees, and the improvements of the HSS and WOMAC scores were 70.06 to 95.72 and 65.64 to 28.92, respectively. CONCLUSION: A surgical robot system that has the ability to execute highly precise preoperative planning and intraoperative procedure for TKA provides good clinical and radiographic results at three years follow-up.