To provide a gypsum plasterboard capable which can be executed of without taking any account of directionality and is excellent in workability.
After a slurry formed by mixing a burnt gypsum with water or the like has been poured on a lower side stencil paper 12L, an upper side stencil paper 12U is overlapped thereon. In that case, the front end in the direction of the width of the upper side stencil paper 12U is overlapped with the side end of the lower side stencil paper to connect. By the constitution, a joint section 13 overlapping the front end edges of the stencils 12 and 12 each other is put on the side of the gypsum plasterboard 10 so that both sides of the gypsum plasterboard 10 become the flat surface capable of being executed on the indoor side. By the constitution, the work is carried out without taking any account of directionality and excellent in workability.