A wireless power transmission system, a method and an apparatus for tracking a resonance frequency in the wireless power transmission system, are provided. A device of the wireless power transmission system includes a resonator configured to receive and output a power from another resonator of another device. The device further includes a power supply unit configured to provide, to a device load, the power output from the resonator. The device further includes a calibration load configured to receive the power output from the resonator in a calibration mode of the device to match resonance frequencies of the resonator and the other resonator. The device further includes a controller configured to selectively connect the resonator to the power supply unit or the calibration load, based on whether the device operates in the calibration mode.