Provided is an automatic air-extracting sealing box cover, comprising a bottom cover and a top cover that are mutually detachably connected, wherein the bottom cover and the bottom cover are connected to form a device chamber, and an automatic air extracting apparatus is mounted in the device chamber; the automatic air-extracting apparatus comprises a power source, a pressure sensor, an air pump, and a controller; the power source is connected to power source input ends of the pressure sensor, the air pump and the controller; an air extracting opening of the air pump and a probe of the pressure sensor project out of a lower surface of the bottom cover; an output end of the pressure sensor is connected to a collection circuit, and an output end of the collection circuit is connected to an input end of the controller; a control signal output end of the controller is connected an on/off control end of the air pump.