A computer-implemented point cloud data extraction method of extracting target point cloud data as point cloud data as to a specific analysis target from entire perimeter point cloud data acquired by moving a measurement device along a measurement route and scanning a perimeter of the measurement device , the method comprising: acquiring locus point string data representing a locus of movement of the measurement device on the measurement route as a plurality of locus points; setting, as an extraction area, an area positionally defined with reference to each of the locus points of a locus point string acquired from the locus point string data and specified by a designated geometrical shape; and extracting, as target point cloud data, point data in the entire perimeter point cloud data belonging to the extraction area, wherein the measurement route is a traveling route on a road as a measurement target and the analysis target is a road surface of the road, characterised in that the extraction area includes a plurality of columnar areas set at positions defined in advance on a vertical line from the locus points and the columnar areas each have set thereto a diameter set in advance and a height dimension set in advance, the extraction area further includes an inner area of a parallelepiped area surrounded by, when attention is focused on adjacent two said columnar areas, two parallel tangent planes circumscribing an outer circumferential plane of each of the two columnar areas, an upper plane corresponding to upper planes of the two columnar areas, a bottom plane corresponding to bottom planes of the two columnar areas, and diameter planes including two generatrixes where the two tangent planes are in contact with the outer circumferential plane in each of the two columnar areas and forming diameters of the columnar areas. acquiring locus point string data representing a locus of movement of the measurement device on the measurement route as a plurality of locus points; setting, as an extraction area, an area positionally defined with reference to each of the locus points of a locus point string acquired from the locus point string data and specified by a designated geometrical shape; and extracting, as target point cloud data, point data in the entire perimeter point cloud data belonging to the extraction area, wherein the measurement route is a traveling route on a road as a measurement target and the analysis target is a road surface of the road, characterised in that the extraction area includes a plurality of columnar areas set at positions defined in advance on a vertical line from the locus points and the columnar areas each have set thereto a diameter set in advance and a height dimension set in advance, the extraction area further includes an inner area of a parallelepiped area surrounded by, when attention is focused on adjacent two said columnar areas, two parallel tangent planes circumscribing an outer circumferential plane of each of the two columnar areas, an upper plane corresponding to upper planes of the two columnar areas, a bottom plane corresponding to bottom planes of the two columnar areas, and diameter planes including two generatrixes where the two tangent planes are in contact with the outer circumferential plane in each of the two columnar areas and forming diameters of the columnar areas. <EOS>