1. A face authentication system, comprising: a data input section for obtaining three-dimensional data concerning a face area of a subject at multiple points; and a processor for performing a registration process or a verification process of authentication data of the subject based on the three-dimensional data, the processor including: a quality rater for rating a quality of the three-dimensional data with respect to a specified number of points of the three-dimensional data to generate quality data; and a quality distribution deriving section for deriving a distribution of the quality with respect to the face area, based on the quality data.