1. A method for detecting an eye position from a face image including at least an eye area, comprising the steps of: performing brightness correction for part or the entire of the face image to increase the contrast between a sclera portion and an iris portion of the eye; calculating brightness gradient vectors for the brightness-corrected face image; and performing matching between a brightness gradient image generated using the calculated brightness gradient vectors and an eye template, wherein the eye position is detected based on the results of the matching.