A detection device capable of reliably detecting an object to be detected. An intersection region pattern setting unit (106) sets a configuration pattern of a first intersection region pattern group in sequence for each unit image pair. Each intersection region pattern is defined by set image information which denotes locations and sizes of regions (where n is a natural number greater than 1) within respective unit images (e.g., unit image plane coordinates), as well as whether each region is set within either or both of a first unit image and a second unit image. A detection unit (108) detects the object to be detected, based on a total feature value relating to each configuration pattern of the first intersection region pattern group, computed by a feature value computation unit (107), and a strong identification apparatus configured from a plurality of weak identification apparatuses and stored in an identification apparatus storage unit (112).