Even when a driver is not directing his or her line of sight to objects in the surroundings, the amount of attention of the driver to the peripheral visual region is to be determined, and safe driving assistance is to be provided in accordance with the result of determination.A driving attention amount determination apparatus includes: an electroencephalogram measurement section for measuring an electroencephalogram signal of a driver a central stimulation presentation section for presenting a visual stimulation in a central visual field of the driver a peripheral stimulation presentation section for presenting a visual stimulation in a peripheral visual field of the driver a threshold setting section for setting a determination threshold for attention amount determination from a distribution of amplitude of an event-related potential in the electroencephalogram signal based on a point of presenting the stimulation in the central visual field as a starting point and an attention amount determination section for determining an attention amount through a comparison between the determination threshold and an amplitude of an event-related potential in the electroencephalogram signal based on a point of presenting the stimulation in the peripheral visual field as a starting point.