There is provided a technique to correctly select and measure a pattern to be measured even when contours of the pattern are close to each other in a sample including a plurality of patterns on a substantially same plane.A pattern measuring apparatus that scans a sample with charged particles, forms a detected image by detecting secondary charged particles or backscattered charged particles generated from the sample, and measures a pattern imaged on the detected image includes: an image acquiring section acquiring a plurality of detected images taken at a substantially same location on the sample under different imaging conditions; a contour extracting section extracting a plurality of pattern contours from the plurality of detected images; a contour reconstructing section reconstructing a contour to be measured by combining the plurality of pattern contours; and a contour measuring section making a measurement using the reconstructed contour to be measured.