Disclosed is an autonomous driving device (100) in which a threshold value (Tth) for switching to manual driving which is used for switching a driving state from autonomous driving to manual driving with respect to degree to which a steering operation is carried out by a driver is calculated to be a greater value by a calculation unit (14) when the direction of the steering operation is predicted to be a direction close to an obstacle than a threshold value when the direction of the steering operation is predicted to be a direction away from the obstacle or a threshold value when no obstacle is detected.