A start control method for a vehicle, comprising the following steps: when a door of the vehicle is in an open state, determining a position of a key; controlling, if the key is in the vehicle, a first high-voltage module group of the vehicle to perform power on; and when the door of the vehicle is changed from the open state to a closed state, determining the position of the key and detecting a state of a brake pedal of the vehicle; and if the brake pedal of the vehicle is depressed and the key is in the vehicle, controlling, according to a start instruction, a second high-voltage module group of the vehicle to perform power on, wherein the first high-voltage module group comprises a vehicle control unit, a battery management system, and a motor controller, wherein the controlling a first high-voltage module group of the vehicle to perform power on comprises: controlling the vehicle control unit, the battery management system, and the motor controller to respectively perform power-on self-check; and after the power-on self-check is completed, controlling, by the vehicle control unit, the battery management system to perform pre-charging, and the battery management system pulling in a main contactor upon completion of the pre-charging, wherein the second high-voltage module group comprises a transmission control unit and an engine control module, and the controlling a second high-voltage module group to perform power on comprises: controlling the transmission control unit and the engine control module to perform power-on self-check. when a door of the vehicle is in an open state, determining a position of a key; controlling, if the key is in the vehicle, a first high-voltage module group of the vehicle to perform power on; and when the door of the vehicle is changed from the open state to a closed state, determining the position of the key and detecting a state of a brake pedal of the vehicle; and if the brake pedal of the vehicle is depressed and the key is in the vehicle, controlling, according to a start instruction, a second high-voltage module group of the vehicle to perform power on, wherein the first high-voltage module group comprises a vehicle control unit, a battery management system, and a motor controller, wherein the controlling a first high-voltage module group of the vehicle to perform power on comprises: controlling the vehicle control unit, the battery management system, and the motor controller to respectively perform power-on self-check; and after the power-on self-check is completed, controlling, by the vehicle control unit, the battery management system to perform pre-charging, and the battery management system pulling in a main contactor upon completion of the pre-charging, wherein the second high-voltage module group comprises a transmission control unit and an engine control module, and the controlling a second high-voltage module group to perform power on comprises: controlling the transmission control unit and the engine control module to perform power-on self-check. controlling the vehicle control unit, the battery management system, and the motor controller to respectively perform power-on self-check; and after the power-on self-check is completed, controlling, by the vehicle control unit, the battery management system to perform pre-charging, and the battery management system pulling in a main contactor upon completion of the pre-charging, wherein the second high-voltage module group comprises a transmission control unit and an engine control module, and the controlling a second high-voltage module group to perform power on comprises: controlling the transmission control unit and the engine control module to perform power-on self-check.