To provide a brain-image diagnosis supporting method or the like. The method is a statistical evaluation method excluding the subjective judgment of an examiner, and enables image diagnosis. The method can present stable judgment criteria with respect to data on brain images imaged by a predetermined method in order to discriminate difficult diseases to diagnose. The method is also effective with respect to relationships which can not be always explained with a simple linear relationship, for example, the relationship between data on brain images imaged by a predetermined method and a disease which is a variable. By applying a predetermined nonlinear multivariate analysis method to data on brain images of a plurality of examinees imaged by a predetermined method and by classifying the data, image diagnosis support using a computer performed with respect to the data on brain images is performed. For example, SOM method is applied as a predetermined nonlinear multivariate analysis method. Data on brain images of a plurality of examinees imaged by SPECT or the like are handled as input data vectors x, which are presented to neurons on a two-dimensional lattice array in the SOM method so as to perform image diagnosis support based on the two-dimensional SOM after a predetermined training length.