1. A method of detecting a position of a face feature point by using an Adaboost learning algorithm, the method comprising: (a) classifying a sub-window image into a first feature point candidate recommendation image and a first feature point candidate non-recommendation image by using first feature patterns selected through the Adaboost learning algorithm, and generating first feature point candidate position information of the first feature point candidate recommendation image; and (b) re-classifying the sub-window image classified as the first feature point candidate non-recommendation image into a second feature point candidate recommendation image and a second feature point candidate non-recommendation image by using second feature patterns selected through the Adaboost learning algorithm, and generating second feature point candidate position information of the second feature point candidate recommendation image.