Contactless power supply system

A contactless power supply system that supplies, in a contactless manner, power from a power supply device in a road on which a vehicle travels to a power reception device in the vehicle, wherein

• the power supply device includes:
• a first communication device that executes a wide-area wireless communication with the power reception device;
• a second communication device that executes a short-range wireless communication with the power reception device;
• and
• an acceptable value deriving unit that derives an acceptable value of a power change rate feasible in the power reception device,
• the power supply device transmits information regarding the acceptable value of the power change rate derived by the acceptable value deriving unit to the power reception device by using at least one of the first communication device and the second communication device, and
• the power reception device executes power control within a range not exceeding the acceptable value based on the information regarding the acceptable value of the power change rate received by the power reception device.