A device and a method for controlling OTA update of a vehicle, to automatically set an optimal current consumption regardless of a vehicle model and an option for each vehicle model, includes a sensor configured for measuring a current consumption of a battery provided in the vehicle, and a controller that sets an initial current consumption to the vehicle, determines whether the OTA update is possible based on the initial current consumption and an expected over the air (OTA) update time, and determines an optimal current consumption based on the initial current consumption and an average current consumption during the OTA update.