The reduction of magnetic field strength at the center of a shielding box located in a uniform magnetic field has been reported in many studies. The space in the box was completely enclosed by magnetic materials to effectively reduce penetration of outside magnetic fields into the box. This conventional sealed box method is thought to be complicated for practical use. In contrast, this study proposes the magnetic shielding box to be a ldquolattice frame structurerdquo using the open-type magnetic shielding method. Each lattice contains the same structure in which closed-loop frames align to form a box with gaps. Small, medium, and large lattice boxes are put together with the center axes orthogonal to each other. This study reports magnetic shielding performance for the open-type magnetic shielding boxes of single, double, and triple lattice frames in a uniform magnetic field with some experimental comparison to the conventional sealed box method.