A shape evaluation device performs simulation by using an annular light source or concentric light source instead of a rectilinear light source and calculates a characteristic line for performing shape evaluation. The shape evaluation device includes a calculation device (2) having: a distance vector calculation unit (2a) for acquiring a distance vector representing a distance between the circle and the vector, a distance function unit (2b) for acquiring a distance function from the distance vector, and a distance function calculation unit (2c) for acquiring a point on a curved surface where the value of the distance function is a predetermined value. By performing simulation using the annular or concentric light source, it is possible to obtain a characteristic line capable of observing distortion in all the directions by one calculation. The present invention reduces the number of calculations required for calculating the characteristic line for performing shape evaluation and reduce the time required for calculation, thereby enabling evaluation by a dynamic shape.