A control device for a vehicle executes an adaptive cruise control and an idle stop control. The control device automatically starts an internal combustion engine when an operation amount of a start operating member different from a brake pedal is larger than or equal to a predetermined amount while the idle stop control is being executed. The control device sets the predetermined amount to a first predetermined amount when the adaptive cruise control is not executed. The control device sets the predetermined amount to a second predetermined amount smaller than the first predetermined amount when the adaptive cruise control is being executed.