To provide equipment which automatically opens the mouth of a sheet-shaped bag body and keeps its mouth in an open condition, capable of easily inserting a vegetable, food or other products in the sheet-shaped bag body.

An air blower which opens the mouth of a bag body 3 by blasting air toward the mouth end of the bag 3 caught by a catching part 20 along a fitting base 1 in a state in which the mouth end side can be opened is provided. A guide part 28, comprising a surface guide part which guides an air blast in a direction along the base face of the fitting base 1 into the bag body 3 and a mouth guide part which guides in a direction to push open the mouth end of the surface side of the bag body 3 from the side of the fitting base 1, is provided at the upper stream of the air blast.