A three-dimensional data generation device includes a virtual space arrangement section for arranging a virtual workpiece and a virtual vision sensor in a virtual space so that a part of the virtual workpiece fits in an imaging range of the virtual vision sensor, an arrangement relationship calculation section for calculating an arrangement relation between the arranged virtual workpiece and the virtual vision sensor, and a partial three-dimensional data generation section for generating partial three-dimensional data representing a partial shape of a workpiece which fits in the imaging range based on the calculated arrangement relationship.