A power system of a vehicle includes an engine, a first motor and a second motor. A method for controlling motion of the vehicle includes: receiving a cruise speed, a speed fluctuation quantity and a preset traveling mileage of the vehicle, and obtaining an upper speed bound and a lower speed bound of the vehicle based on the cruise speed and the speed fluctuation quantity; adjusting a current speed of the vehicle to the lower speed bound, and controlling the vehicle to enter a first cruise phase of a two-phase cruise mode; and controlling the vehicle to enter a second cruise phase of the two-phase cruise mode when the current speed of the vehicle is greater than or equal to the upper speed bound and a current traveling mileage is less than the preset traveling mileage.