A packaging box and a method for fabricating the packaging box are provided that reduces a defective fabrication rate from reduced wrinkling and cracks. A V-shaped cut groove is formed to extend in one direction by cutting an outer surface of an inner layer, a curved groove having a curved surface is formed to extend in parallel with the cut groove by pressing an inner surface of the inner layer, and the inner layer is bent with respect to the curved groove. The curved groove is at an offset position with respect to the cut groove.