The invention relates to a power-on and power-off control method for an electric automobile. The method includes the steps that a BMS or an automobile
control unit is adopted to monitor the interval time between a received power-on instruction and a received power-off instruction; if the interval time is larger than or equal to a certain threshold value, power-on or power-off operation is carried out normally according to the control instruction; if the interval time is smaller than the certain threshold value, a high-
voltage circuit is controlled to be disconnected after time
delay for a period of time, and the preparation for carrying out the power-on operation again is made; if within the
delay time, the BMS or the automobile
control unit receives the power-on instruction or the power-off instruction, the high-
voltage circuit is not disconnected, and the power-on state continues to be kept until the
delay time arrives, and then the high-
voltage circuit is controlled to carry out corresponding operation according to the received instruction. A precharging
resistor of the high-voltage circuit of the electric automobile can be effectively protected and prevented from being damaged, the maintenance cost of the automobile is reduced, and protection of the precharging
resistor plays an active role in protecting the whole high-voltage circuit of the automobile and
electric equipment on the circuit.