An automated driving system includes a determiner, a driving switch controller, and a notification controller. The determiner determines each of a plurality of determination items that is a condition for switching from an automated driving to a manual driving. The driving switch controller switches from the automated driving to the manual driving when all of the plurality of determination items are determined as positive. The notification controller notifies a driver of notification information for urging a reaction of the driver when at least one of the plurality of determination items is determined as negative. The determiner determines the at least one or all of the plurality of determination items before a vehicle passes through a switch determination point. The determiner determines the at least one or all of the plurality of determination items when or after the vehicle passes through the switch determination point.