To provide a USB controller and a method for supplying power to the same, which is capable of eliminating a voltage difference in an interface between a CPU and a USB controller, and free from arranging a means to solve the voltage difference such as a level shift IC, when using a voltage lower than a USB standard to the CPU of a portable electronic apparatus.

The USB controller 7 comprises a USB interface part 3 for performing data communication with a PC 5, a CPU interface part 4 for performing data communication with a CPU 6, a USB interface power input part 8 for supplying power inputted from a USB power supply 10 to the USB interface part 3, and a CPU interface power input part 9 for supplying power inputted from a CPU power supply 11 to the CPU interface part 4, and also has two power input parts for supplying power.