PURPOSE: To provide a low cost packaging case which is excellent in the assembling workability and which can automatically be assembled.

CONSTITUTION: The front side plate 25 is connected to right and left side plates 27, 28 at the first plate-form body 21 side and the bottom plate 35 and the cover plate 36 are connected so as to be folded at the rear side plate 33 in the second plate-form body 22 side. And further, the joining flaps 30 at the ends of both right and left side plates 27, 28 of the first plate-form body 21 are pasted or stuck to the inner surface of the rear side plate 33 of the second plate-form body 22. Moreover, the joining flap 38 at the front end of the bottom plate 35 is pasted or stuck to the outer surface of the front side plate 25.