A control method of a dishwasher that includes at least two flow paths having different flow rates, a chamber having communication holes that each communicate with a respective flow path, a water supply pump configured to supply washing water to the chamber through an impeller rotated by a motor, and a flow path switching unit located within the chamber and configured to sequentially open the communication holes is described. The control method includes the actions of measuring an amount of current supplied to the motor while the motor rotates the impeller to supply washing water to the chamber, and determining a position of the flow path switching unit by comparing the amount of current supplied to the motor with reference current amounts that are each designated as an amount of current supplied to the motor when the motor rotates the impeller to supply washing water to the respective flow path.