1. A design support system comprising: an input portion that receives shape data indicative of at least two, mutually different shapes, finite element model data indicative of a finite element model for each of said at least two shapes, and attribute data indicative of an attribute at each node of the finite element model; a shape display portion that displays said at least two shapes on a screen; a superimposing portion that superimposes said at least two shapes displayed on the screen by the shape display portion, on each other, with reference to a site designated by information received by the superimposing portion, or a predetermined site; an attribute calculating portion that calculates the attribute at an attribute calculation point set at a predetermined position on the screen, based on the attribute of said each node, with respect to each of said at least two shapes superimposed on each other; and an attribute difference calculating portion that calculates differences in the attribute between said at least two shapes, at the nodes and the attribute calculation points.