There is provided a platemaking method of forming relief based on relief pattern data in a printing plate to be pressed on a printing matter, and the platemaking method includes the steps of: estimating distribution of printing pressure of the printing plate pressed on the printing matter on the basis of image data; calculating an amount of correction of engraving shape data on the basis of the distribution of printing pressure; correcting the engraving shape data on the basis of the amount of correction; and acquiring exposure amount data from the engraving shape data corrected. By exposure (engraving) processing based on the exposure amount data that can be acquired in this way, it is possible to form relief in consideration of deformation of a printing plate in accordance with the distribution of printing pressure in the printing plate to favorably print and reproduce an image on a printing medium.