An image processing apparatus in which an appropriate color separation table is selected for an unexpected print medium. In plural color separation tables 108, maximum total color-material color discharge amounts are set to be stepwisely different. A .gamma. correction table 109 is used upon correction of .gamma. characteristics of the respective color-material colors regarding a print medium. A maximum total ink-amount calculation unit 110 calculates a maximum value of total ink amount for each color separation table 108 by using the .gamma. correction table 109. A color separation table selector 107 determines a maximum value approximate to a value set by a maximum total ink-amount setting unit 106 from the calculated maximum values, and selects a color separation table corresponding to the determined maximum value. A color separation processor 102 performs processing based on the selected color separation table.