A single stacking element structure is cut from a truncated regular octahedron. The single stacking element structure includes a surface having a regular hexagonal shape and three surfaces having regular quadrilateral shapes. The surface having a regular hexagonal shape is connected to the three surfaces having the regular quadrilateral shapes. A closed line is formed on six surfaces of the truncated regular octahedron having the regular hexagonal shapes. The closed line is passed through a center point of a connecting edge between any adjacent two of the six surfaces having the regular hexagonal shapes. A geometric center point of the truncated regular octahedron is connected to a plurality of points of the closed line to form a plurality of connecting lines. The connecting lines form a plurality of cutting surfaces. The single stacking element structure is cut into one of two three-dimensional structures from the truncated regular octahedron according to the cutting surface, so that the single stacking element structure is half of the truncated regular octahedron. Therefore, the present disclosure uses a special solid as a single element structure, and a plurality of single element structures can be combined to form different structures to achieve particular configurations. In practice, the single stacking element structures can be both educational and fun, as users can develop cognition of space geometry, organization structure and creativity at the same time. |