DRIVING ASSISTANCE DEVICE AND DRIVING ASSISTANCE METHOD

An acquisition unit (720) acquires a light path length rijcorresponding to an emission direction (αi, βj) of emitted light, which is surrounding information of a moving body obtained by using a laser radar (910) mounted on the moving body, a traffic mirror information including a center position N of a traffic mirror on a map, and position information of the moving body on the map. Then, on the basis of the acquired traffic mirror information and the acquired position information of the moving body on the map, an extraction unit (730) extracts a light path length acquired via the traffic mirror from the acquired light path length rij, and then calculates an object reflection position corresponding to the extracted light path length. As a result, it is possible to obtain surrounding in formal ion in a blind spot for a driver while increasing robustness with respect to the surrounding information, and thus advanced driving assistance can be implemented.