The invention provides a car following control method and device for autonomous carand the car, so as to achieve the effect of improving movement smoothness of the car when a car following target is switched. The method comprises the following steps: whether the car following target of the car is switchedis detected when the car is in a stable car following working condition; in case of switching,the starting speed of the car,the starting speed of a preceding car, the starting following distance between the car and the preceding car and the target following distance after switching of the carfollowing target are detected; if the starting speed of the preceding car is higher than that of the car, an isosceles trapezoid acceleration curve is planned, and the caris controlledaccording to target expected acceleration obtained by the isosceles trapezoid acceleration curve; if the starting speed of the preceding car is lower than or equal to the starting speed of the car, an isosceles trapezoid deceleration curve is planned, and the car is controlled according to the target expected acceleration obtained by the isosceles trapezoid deceleration curve.