PURPOSE: To review the results in the management of ipsilateral femur and tibia fractures, using femoral and tibial intramedullary nailings with single incision on the knee. MATERIALS AND METHODS: We treated 19 cases of ipsilateral femur and tibia fractures (floating knee), and the retrograde femoral nailing and antegrade tibial nailing were done with single incision on the knee. Except one patient of early death, 18 patients were included in this study. The mean age of index procedure was 34.1 years, and all of them had follow-up study for a mean of 2.4 years. The mean injury severity score was 18.8, and 12 patients had other fractures in the lower extremity. RESULTS: Primary union was achieved in all, but one patient of femur and two of tibia. The average period for union was 27.6 weeks for femur and 24.5 weeks for tibia. One femoral nonunion occurred due to the metal failure after using short nail, and two tibial nonunion were caused by the bone loss with open tibial fractures. Most patients showed no limitation in knee motion. According to Karlstrom-Olerud criteria, functional results showed 14 excellent, 3 good and 1 acceptable. The protrusion of nail tip into the knee joint made the acceptable result with moderate limitation of knee motion, but it improved after the removal of nail. CONCLUSION: CONCLUSION: Simultaneous retrograde femoral and antegrade tibial nailing with single incision on the knee, with an appropriate technique, can achieve the satisfactory result in the management of the ipsilateral femur and tibia fractures.