Abstract: An object of the present invention is to build a simulated image in which a subject's hair is changed to a desired color, and to accurately suggest the hair dye needed to dye the subject's hair from its existing color to the desired color. To achieve this object, the hair color advice system according to the present invention includes (i) an image memory into which image data regarding the subject is input and stored, (ii) a processor that finds the hair area in the input image of the subject and builds a simulated image in which the color of the hair area is changed to any color, and (iii) a monitor 4 on which the input image of the subject and/or the simulated image are displayed.