A near-infrared night vision device to which a pedestrian detection device is applied includes a near-infrared projector, a near-infrared camera, a display and an ECU. By executing programs, the ECU constitutes a pedestrian candidate extraction portion and a determination portion. The pedestrian candidate extraction portion extracts pedestrian candidate regions from near-infrared images. The determination portion normalizes the sizes and the brightnesses of the pedestrian candidates extracted by the pedestrian candidate extraction portion, and then computes the degrees of similarity between the normalized pedestrian candidates. The determination portion determines that a pedestrian candidate having two or more other pedestrian candidates whose degree of similarity with the pedestrian candidate is greater than or equal to a predetermined value is not a pedestrian.