Water mist generating device, hydration negative oxygen ion generator and air purifier

The utility model relates to a water mist generating device, a hydration negative oxygen ion generator and an air purifier. The water mist generating device comprises a base, a mounting seat; an atomization sheet; the base is provided with a through hole capable of communicating the cavity with the mounting cavity, the base is provided with a first positioning part, the mounting seat is provided with a second positioning part, and the mounting seat can rotate around the axis of the through hole to a first state in which the first positioning part is connected with the second positioning part and a second state in which the first positioning part is separated from the second positioning part. By rotating the mounting base, the mounting base and the connecting base can be disassembled and assembled, compared with a screw connection mode, the mounting base and the connecting base are convenient to use, and the first positioning part is arranged on the base, and the second positioning part is arranged on the moun