To provide a paper catch box for aligning four corners of papers by assembling an original product obtained by pressing a piece of cardboard or a piece of corrugated cardboard.

A long side surface 2 of a pressed original cardboard is bent at a right angle along a fold line 6. A short side surface 3 is bent at a right angle along the fold line 6. A cut opening 10 is overlapped on a place where the tongue piece 7 of the long side surface 2 is formed to fix the tongue piece 7 by bending. Two holding parts 8 are bent upward to reinforce the short side surface 3. A finger insertion hole 9 is aligned to reinforce a place into which the finger is inserted.