1. A similar image search system comprising an image database which stores a number of pieces of image data representing a number of images, an image input means for inputting search image data representing the whole and/or a part of an image an image similar to which in feature is to be searched for, a searching means which searches the database for similitude image data representing an image which is similar to an image represented by the input search image data in feature, and a search report output means which outputs a search report representing result of search by the searching means.