We describe a strategy of scaffolded DNA origami to design and construct 3D molecular cages of tetrahedron geometry with inside volume closed by triangular faces. Each edge of the triangular face is ∼54 nm in dimension. The estimated total external volume and the internal cavity of the triangular pyramid are about 1.8 × 10⁻²³ and 1.5 × 10⁻²³ m³, respectively. Correct formation of the tetrahedron DNA cage was verified by gel electrophoresis, atomic force microscopy, transmission electron microscopy, and dynamic light scattering techniques.