A vehicle monitoring device includes a determination unit that determines whether a following vehicle shown in an image taken by a camera that takes an image of a surrounding area of a host vehicle is a two-wheel vehicle or not, and a warning unit that issues a warning when an inter-vehicle distance between the following vehicle and the host vehicle becomes equal to or less than a first distance in a case where the following vehicle is determined not to be a two-wheel vehicle by the determination unit, and issues a warning when the inter-vehicle distance between the following vehicle and the host vehicle becomes equal to or less than a second distance, which is longer than the first distance, in a case where the following vehicle is determined to be a two-wheel vehicle by the determination unit.