Driving assistant apparatus

The present invention relates to a driving support device. The driving support device includes: a sensing unit which detects the distance to another vehicle and the distance to a final lane based on image information output from a front sensing device of a vehicle having the driving support device mounted thereon; a first calculation unit which uses a present visible distance constant and the distance to the final lane to calculate the visible distance of a driver; a second calculation unit calculating the speed (v0), which satisfies an inequation represented as [] as a safe speed when the shortest distance to a preset area of interest is greater than the visible distance of the driver and the distance to the other vehicle is equal to or greater than the visible distance of the driver; and a providing unit providing the safe speed to the driver. The inequation includes deceleration and acceleration rate (abreak) of the vehicle known in advance, the reaction time of the driver (treact) known in advance, the visible distance of the driver (dVRH), and the speed of the vehicle (v0).