1. A computer-implemented image searching method of searching for a desired image in an image database which stores a plurality of images each having predetermined color information signals containing a plurality of color components, by using an input color information signal containing a plurality of color components, comprising: an image searching computer-implemented first step of calculating a contribution factor of each color component of color information on the basis of the input color information signals; an image searching computer-implemented second step of calculating a similarity between the input color information signal and the plurality of predetermined color information signals based on said contribution factor of each color component of the color information signals, as calculated at said image searching computer-implemented first step; and an image searching computer-implemented third step of sorting said plurality of predetermined color information signals based on an order of similarity as calculated at said image searching computer-implemented second step, and of displaying the sorted predetermined color information signals on a display means; and an image searching computer-implemental fourth step of selecting one of the displayed sorted predetermined color information signals as the desired image.