A color adjustment apparatus includes a pair generating section, a vector generating section, a weight calculating section, a synthesized-vector generating section and a color converting section. The pair generating section generates pairs of colors in a first color gamut and corresponding colors in a second color gamut. One of the pairs includes white in the first color gamut. The vector generating section generates plural vectors each connecting the color in the first color gamut and the color in the second color gamut, which belong to each generated pair. The weight calculating section calculates weights in accordance with distances between a color, which is to be processed and is in the first color gamut, and origins of the generated vectors. The synthesized-vector generating section applies each calculated weight to the corresponding vector to generate a synthesized vector. The color converting section converts the color to be processed using the synthesized vector.