An obstacle detection apparatus includes an image input unit inputting a image sequence captured by an image sensor, a velocity detector deriving velocity vectors representing motions of a to-be-detected point and a to-be-compared point on each image of the image sequence, a predictive velocity vector calculator calculating a predictive velocity vector of the to-be-detected point using a detected velocity vector of the to-be-compared point, an obstacle detector detecting the to-be-detected point as a point on the obstacle when a horizontal component of a detected velocity vector of the to-be-detected point is larger than a horizontal component of the predictive velocity vector by a given threshold, and an obstacle information output unit outputting information on the to-be-detected point detected as the obstacle.