An apparatus for controlling a drive motor of a vehicle in which a wound rotor synchronous motor is mounted includes: an inverter which controls a stator current supplied to a stator of the drive motor and a rotor current supplied to a rotor of the drive motor; and a drive motor controller which controls the inverter such that the stator current and the rotor current are supplied to the drive motor when a temperature of the rotor is less than a threshold value, and only the stator current is supplied to the drive motor when the temperature of the rotor is greater than or equal to the threshold value.