Provided is a vehicle periphery monitoring device having: a first distance calculating unit (25) which calculates a distance between a vehicle (10) and an object, using a parallax gradient of image sections of the same object among a plurality of images captured by infrared cameras (2R, 2L) at different times within a predetermined sampling interval; a vehicular velocity sensor (4) which detects a vehicular velocity of the vehicle (10); and a sampling interval setting unit (23) which sets the sampling interval shorter with the increase of the vehicular velocity of the vehicle (10).