[Problem] The purpose of the present invention is to provide a three-dimensional object modeling method which can suppress the occurrence of a streak in a three-dimensional object, such streak being parallel to a primary scanning direction. [Solution] A three-dimensional object modeling method includes: a slice information calculation step (step ST23) of dividing the 3D data of the three-dimensional object into a plurality of layers and then calculating the cross-section slice information of each layer; and a single layer forming step (step ST27) of forming each layer on the basis of the cross-section slice information. The single layer forming step (step ST27) is repeated multiple times. The single layer forming step (step ST27) includes a printing step (step ST27A) of forming a one-line printing pass by causing a discharge unit to move in a primary scanning direction and discharging ink onto a work surface. In the single layer forming step, the printing step and a secondary scanning direction movement step
