1. An apparatus for detecting orientation of a face from image data acquired by photographing the face, the image data being composed of a plurality of pixel data aligned in horizontal direction and vertical direction, respectively, comprising: a horizontal adding section for adding the respective pixel data in the horizontal direction of the image data; an eye detecting section for detecting an eye position in the vertical direction based on a plurality of sum values calculated by said horizontal adding section; an eye vicinity adding section for adding the respective pixel data in the vertical direction in a vicinity region of the eye position detected by said eye detecting section; and an orientation detecting section for detecting a face orientation based on a plurality of sum values calculated by said eye vicinity adding section.