In an image processing apparatus and an image processing method according to the present invention, a gradation correction table creation unit prints stored chart data on a print paper by an image forming device, determines a target color from the color measuring result of the printed chart by a color measuring device, and creates a gray reproduction estimation model function according to the measured color result of the chart. Next, after the gradation correction table is created such that the gray of each gradation is adequately close to the target color, the gradation correction table is changed such that the color difference of neighboring gradations is included in a predetermined range.