A manufacturing method of a heart correction net is provided. The method includes: a first step of taking cross-sectional images of a heart in a layer direction, in which an apex and a base of the heart are connected a second step of extracting outlines of the heart from the cross-sectional images a third step of defining dividing points with respect to a three-dimensional shape reconstructed based on the outlines, the dividing points being defined on the outlines in a circumferential direction of the heart a fourth step of dividing a contour of the heart in three-dimensions into divided regions based on the plurality of the dividing points, and creating development data, in which the each of the divided regions is developed on a two-dimensional plane, while an approximate shape of each of the divided regions is maintained a fifth step of creating paper-pattern data based on the development data and a sixth step of knitting the heart correction net with a knitting machine based on the paper-pattern data.
