PROBLEM TO BE SOLVED: To provide a stacking facility capable of detecting a mistake in holding of a nursery box and preventing the mistake in holding from being erroneously detected due to adhesion of soil or the like.SOLUTION: According to the present invention, a stacking facility comprises: a holding part (420-1, 420-2) for holding a nurturing box (10)； a photoelectric sensor (431) for detecting that the nursery box (10) is mistakenly held by the holding part (420-1, 420-2)； and an air-jetting device (435) for spraying air to the photoelectric sensor (431). In a photoelectric sensor unit (430), a light-projecting surface (431a), and a light-receiving surface (431b) are fixed on the outer surface of the lowermost nursery box (10) held by the holding part (420-1, 420-2). The air-jetting device (435) is arranged at the top of the photoelectric sensor unit (430).SELECTED DRAWING: Figure 4
