This invention relates to a photo-curing modeling apparatus for modeling a three-dimensional shape by inputting tessellation data defining a three-dimensional shape, calculating a profile data for each section on the basis of the tessellation data and controlling a light irradiation region on the basis of the profile data calculated. This apparatus includes means for storing the tessellation data, means for calculating a normal vector at the apex of each tessellation data, means for judging whether the normal vector calculated has a direction extending along the light irradiation direction or an opposite direction, means for offsetting the coordinates of the apex, which is judged as having the normal vector in the light irradiation direction by the judgement means, in the light irradiating direction, and means for calculating the profile data for each section on the basis of the tessellation data thus offset. The shape before offsetting can be accurately embodied.