A package packages an object to be packaged by placing the object to be packaged on a tray box, covering the object with packaging corrugated cardboard from the top, and wrapping a binding band. The packaging corrugated cardboard includes a peripheral wall having a pair of first sidewalls and a pair of second sidewalls, an inner flap connected to a top side of each of the first sidewalls, and an outer flap connected to a top side of each of the second sidewalls. Each inner flap is provided with a pair of protrusions protruding from both side ends of the flap. When the inner flap and then the outer flap are closed, an opening on a top side of the peripheral wall is closed with the protrusions being brought into contact with the second sidewalls.