An occlusion evaluation apparatus capable of evaluating a masticatory ability depending on an occlusal geometry of teeth without actually used by a human subject, reads three dimensional data of geometries of maxillary molar teeth 1, 2, 3, 4 and mandibular molar teeth 5, 6, 7, 8, and specifies a geometry of a fluxion space Va defined by a plane Sa which includes two adjacent contact points Pa between the maxillary molar teeth 1, 2, 3, 4 and mandibular molar teeth 5, 6, 7, 8 and which is perpendicular to the occlusal plane, the occlusal surfaces of the maxillary molar teeth 1, 2, 3, 4, and the occlusal surfaces of the mandibular molar teeth 5, 6, 7, 8.
