Disclosed are a fuse, a fuse box, and a fuse device capable of preventing insertion of wrong products into the box or device and persistent electric arc. In certain aspects, the fuse includes a pair of electro-conductive terminals, a fuse element having a fusion portion provided between the electro-conductive terminals, and an insulating housing mounted so as to cover at least a part of the fusion portion and the electro-conductive terminals, wherein a notch is provided on a lower-end side of the insulating housing, the notch is located between the pair of electro-conductive terminals and at a position that does not interfere with the shape of the fusion portion provided between the pair of electro-conductive terminals, and the notch is formed in a manner that a protrusion provided in a fuse box for housing the fuse can be fitted therein.