A method for recognizing, identifying, and authenticating persons to be identified from their faces in a preset scenario, includes uploading a first image of users to a server, and receiving the first image on which first facial rectangles and user information have been imposed, and capturing a second image and detecting second facial rectangles therefrom. The method determines whether a number of faces of the second image is equal to a number of faces of the first image, and uploading the second image to the server for identifying third facial rectangles of the second image. A plurality of distances is obtained by calculating at least one distance between third and second facial rectangles of each user shown in the second image and determining whether the users shown in the second image are the same as users shown in the first image based on the plurality of distances.