A wave-shaped mask for fabricating a nano-scale structure is disclosed. The wave-shaped mask comprises an elastomeric transparent substrate having an upper surface and a lower surface, and a light-penetrable thin film layer disposed on the upper surface of the elastomeric transparent substrate. The upper surface of the elastomeric transparent substrate and the light-penetrable thin film layer are in a periodic wave shape, and the lower surface of the elastomeric transparent substrate is in a plate shape.