In a vehicular control object determination system, the position of an object detected by a radar device is stored by a detection position memory, and a predetermined area having the position of the object as the center is set as the determination region by a determination region setter. When the determination region set for one of two objects is passed through by the other object, the passing direction is determined by a passing direction determiner. During this process, the direction in which a fixed object or an object dropped on the road moves relative to a preceding vehicle is a direction in which the fixed object or the dropped object on the road approaches the subject vehicle with the preceding vehicle as a reference. Then, a control object determiner excludes from determination of the control object an object for which the passing direction determined by the passing direction determiner is a direction approaching the subject vehicle, thereby preventing the fixed object or the dropped object from being erroneously determined as the control object when the preceding vehicle passes over the fixed object or the dropped object on the road.