A color conversion method including the steps of a) generating output values corresponding to a body-center of each cubic lattice block included in a three-dimensional input space, and interpolating between the output values generated in step a) and the LUT values. The cubic lattice block is divided into six quadrangular pyramids. Each of the quadrangular pyramids is divided into two tetrahedron blocks by a side parallel to a predetermined straight line and by a plane including a diagonal line of a bottom plane that intersects the side parallel to the predetermined axis. Corrected output values are determined by performing linear interpolation on output values corresponding to body-center points of each of the tetrahedron blocks and using LUT values corresponding to three lattice points of each of the tetrahedron blocks and three correction coefficients based on a positional relationship of input color signals inside each of the tetrahedron blocks.