The automatic cover plate comprises a base, a seat ring and a
toilet cover, the base is provided with an
air compression device and a pneumatic limiting device, the
air compression device is provided with an air return structure, and the pneumatic limiting device is provided with a slow leakage valve; the seat ring is rotatably mounted on the base, and the seat ring in a seated state can close the slow leakage valve; the
barrel cover is rotationally installed on the base and is in transmission fit with the
air compression device, a first reset structure matched with the pneumatic limiting device is arranged between the
barrel cover and the base, and when the
barrel cover rotates from the closed position to the open position, the barrel cover drives the air
compression device to exhaust air in the air
compression device to the pneumatic limiting device through the first flow channel; the pneumatic limiting device is driven to limit work of the first reset structure. According to the automatic cover plate, the barrel cover can be automatically closed after a period of time of
defecation of a user, the problem that the user forgets to cover the barrel cover after
defecation is solved, and the user is allowed to open or close the barrel cover at any time according to needs.