Method for providing augmented reality by using image feature, server and portable terminal therefor

PURPOSE: A method for providing augmented reality by using an image feature, a server thereof and a portable terminal thereof are provided to transfer some of acquired image information from a portable terminal to an AR(Augmented Reality) server. CONSTITUTION: A server control unit(220) extracts a specific image feature point from image information of a portable terminal, and compares extracted specific image feature point with pres-stored location-based information. The server control unit extracts the region information data and the extracted image feature point. The server control unit transfers the extracted local information data to the portable terminal, and the portable terminal transfers some of the acquired image in the transmission of the image information.