In this article, an extraction method of line contour points from point cloud data (for a fold-line edge and a ridge edge with a small chamfer) is proposed. In this method, multiple-direction slices were constructed to obtain section data containing line contour points. Then, according to the form characteristic of the section data, a pattern vector was constructed by using the normal angle of two adjacent points to represent the characteristic. The section data was divided into many small groups, each with the same number of components. Euclidean distances between the pattern vector and each small group were calculated, and the group with the smallest Euclidean distance was located for picking out the line contour point. To determine the accuracy of the proposed method, examples of three kinds of edges were used: a straight-line edge, a curve edge, and four circles. The extracted line contour points were fitted to a straight line, a three-order polynomial, and circles, by the least square fitting method. The deviations of the line contour points to the fitted lines were calculated. The standard deviations of the straight-line and curve edges were 0.076 and 0.047 mm, respectively. The standard deviations of the four circles were smaller than 0.1 mm. The radius deviation of the four circles to the reference data, measured by a coordinate measuring machine, was within 0.1 mm. This pattern vector method is applicable for extracting line contour points on a fold-line edge and a ridge edge with a small chamfer. When the scanning accuracy is higher than 0.03 mm, the pattern vector method ensures an accuracy of 0.1 mm.