A user terminal according to an embodiment of the present invention includes a content providing unit for displaying a text-type advertisement content on a lock screen according to an input of a user, a gaze tracking unit for acquiring, through a photographing device, a face image of the user and a vector indicating a direction in which a face of the user faces, and tracking a gaze of the user from the face image and the vector, so as to determine whether the user has read the text-type advertisement content, and a reward providing unit for providing a set reward when it is determined that the user has read the text-type advertisement content. A text-reading based reward-type advertisement service may be provided with the user terminal.