A wireless power transmitting apparatus converts rotational energy of an axle to electrical energy, transfers the electrical energy to a transmitting coil of the wireless power transmitting apparatus through a power transfer connection pin that connects the inside of the wheel and the outside of the wheel of a vehicle, and wirelessly transmits the electrical energy to the sensor using resonance between a transmitting coil of the wireless power transmitting apparatus and a receiving coil of the sensor in order to use it as a driving power source of a sensor that detects a state of a tire.