The invention provides an inverter protection method, a protection device and an electric vehicle. The method comprises the following steps: the power grid voltage at the AC side of the inverter is sampled; according to the power grid voltage, the change rate of the power grid voltage is acquired, and whether the change rate of the power grid voltage is larger than or equal to a preset voltage change rate is judged; and if the change rate of the power grid voltage is larger than or equal to the preset voltage change rate, over-current protection control is carried out on the inverter. According to the inverter protection method of the embodiment of the invention, the speed of carrying out over-current protection on the inverter can be improved, and the safety and the reliability of an inverter circuit can thus be improved.