A detection device (10) according to the present disclosure includes an acquisition unit (11) that acquires point cloud data indicating a distance from a measurement device to an object and luminance information obtained from reflected light of a beam emitted when the point cloud data is measured, an edge detection unit (12) that performs edge detection based on the luminance information, and a crack determination unit (13) that determines whether an area indicates a crack by using a shape of the area in which, of a plurality of points indicated by the point cloud data, points having luminance within a predetermined range of difference from luminance of a point detected as an edge are distributed.