PURPOSE: To enable controlling characteristics which are capable of effecting a satisfac tory speed control, to be set with ease by configurating a device in such a way that, when a car speed control is inoperative, the characteristics of a car speed corresponding to the manipulated variable of an accelerator has been learned in advance, and the said characteristics are used for the car speed control.
CONSTITUTION: The manipulated variable of an accelerator is detected by an accelerator manipulated variable detecting means (a), and the car speed is detected by a car speed detecting means (b). A speed control means C allows the car speed to be controlled so as to be a target speed by means of the characteristics of the car speed corresponding to the manipulated variable of the accelerator. The mentioned characteristics are learned by a characteristics learning means (d) by means of both the manipulated variable of the accelerator and the car speed, both of which are detected when the said car speed controlling means is inoperative. In addition, the weight of the car is measured by a car weight detecting means (e), and when a change in weight is detected, a command for restarting learning the characteristics is directed to the characteristics learning means (d) by a restart characteristics learning means (f).