Autonomous driving assistance devices, methods and programs generate assistance information to be used in autonomous driving assistance that is executed in a vehicle. The devices, methods and programs set a target travel trajectory that is an aimed travel trajectory for a road on which the vehicle travels and set a control target point to a position that is located on the target travel trajectory and ahead of a trajectory generation start point in a direction in which the vehicle is traveling based on a type of autonomous driving assistance being executed in the vehicle. The devices, methods and programs generate a control trajectory to be followed by the vehicle by using a trajectory from the trajectory generation start point to the control target point.