An automated driving device includes: a navigation unit configured to retrieve one or more partial routes with a predetermined length other than a guide route which branch from the guide route at a branch point through which a vehicle is expected to pass before the vehicle passes through the branch point; and an electronic control unit configured to control automated driving of the vehicle based on information of a specific partial route out of the one or more partial routes in a period until the navigation unit completes retrieval of a redundant route for guiding the vehicle to a destination point when the vehicle departs from the guide route at the branch point and travels on the specific partial route.