A control method of an electric vehicle, comprising: operating, by a controller, a battery and a motor; detecting, by the controller, a torque command, a motor speed, and a motor current; calculating, by the controller, a motor voltage from the motor current; determining, by the controller, whether voltage utilization based on a speed range of the motor is greater than a predetermined value; generating, by the controller, an operating point correcting function based on the motor speed in response to the voltage utilization being less than the predetermined value; calculating, by the controller, a current command according to the motor speed from the operating point correcting function; and outputting, by the controller, the calculated current command; wherein the generating of an operating point correcting function, includes: setting, by the controller, a current map with respect to a first motor speed; calculating, by the controller, a first magnitude of a first d-axis current and a first q-axis current, and a first angle of the first d-axis current and the first q-axis current within a synchronous reference frame with respect to a torque command at the first motor speed; setting, by the controller, an operating point with respect to a second motor speed; calculating, by the controller, a second magnitude of a second d-axis current and a second q-axis current, and a second angle of the second d-axis current and the second q-axis current with respect to the second motor speed; calculating, by the controller, a difference between the first and second current magnitude and a difference between the first and second current angle; and calculating, by the controller, the operating point correcting function by approximating the difference of the current magnitude and the difference of the current angle. operating, by a controller, a battery and a motor; detecting, by the controller, a torque command, a motor speed, and a motor current; calculating, by the controller, a motor voltage from the motor current; determining, by the controller, whether voltage utilization based on a speed range of the motor is greater than a predetermined value; generating, by the controller, an operating point correcting function based on the motor speed in response to the voltage utilization being less than the predetermined value; calculating, by the controller, a current command according to the motor speed from the operating point correcting function; and outputting, by the controller, the calculated current command; wherein the generating of an operating point correcting function, includes: setting, by the controller, a current map with respect to a first motor speed; calculating, by the controller, a first magnitude of a first d-axis current and a first q-axis current, and a first angle of the first d-axis current and the first q-axis current within a synchronous reference frame with respect to a torque command at the first motor speed; setting, by the controller, an operating point with respect to a second motor speed; calculating, by the controller, a second magnitude of a second d-axis current and a second q-axis current, and a second angle of the second d-axis current and the second q-axis current with respect to the second motor speed; calculating, by the controller, a difference between the first and second current magnitude and a difference between the first and second current angle; and calculating, by the controller, the operating point correcting function by approximating the difference of the current magnitude and the difference of the current angle.