Concerning the power consumption of routers based on Network on Chip (NoC), the key factors that influence the router power consumption were studied on the systematic level, such as the number of virtual channels, the depth of buffer and the width of flit. A method of reducing power consumption was presented by incorporating various key factors of power consumption and making the virtual channels share the switch input port. And then a NoC-based router with low-power consumption was implemented. The experimental results show that the designed router has lower power consumption in comparison with the Alpha 21364 router and the IBM InfiniBand router.