To solve the following problem: only display of curvature information indicating a locus of data of a moving position command included in an NC program or how it changes, as usual, cannot easily grasp moving situations of each driving shaft of a machine.

A display method of the NC program includes: an interpolation process S11 for calculating a moving target position of each driving shaft according to the NC program by using the same interpolation algorithm and group of NC parameters as an NC device; a feed rate calculation process S12 for calculating a feed rate on the basis of the moving target position and an interpolation cycle in the group of NC parameters; and a display process S13 for displaying at least one component value of either the moving target position of each driving shaft, a moving route between the positions, or feed rate at the moving position according to display attribute defined by one or more component value or size of the feed rate on the basis of a designated point of view direction, display range, and magnifying power.