To provide an apparatus for opening an opening part of a bag body made of a laminated resin capable of opening the opening parts of a plurality of the laminated bag bodies made of the resin under a condition that both side faces are tightly stuck together, taking out only the bag body of the uppermost layer, and rapidly and easily performing a bag filling operation.

The apparatus for opening the opening part of the bag body made of the laminated resin is composed of a pressing means for pressing a specified position of the bag body made of the laminated resin, a sticking means for sticking the neighborhood of the opening part of the surface side sheet of the bag body made of the resin of the laminated uppermost layer, and an elevating/lowering means for opening the opening part of the bag by elevating/lowering the sticking means and by taking up the surface side sheet of the bag body made of the resin of the uppermost layer.