Abstract: A vacuum canister comprises a container and a lid which is provided with a large slot having centrally in the bottom thereof a retaining hole provided peripherally with ventilation holes. A soft disk member is provided such that a retaining column of the disk member is held in the retaining hole of the large slot of the lid, and that a disk portion of the disk member is located on the ventilation holes. The lid is further provided with a suction unit comprising a lever and a suction block. The lever is fastened pivotally at one end thereof to the lid and is provided on another end thereof with a hand grip. The suction block is fastened pivotally to the midsegment of the lever and is provided with a rod and a piston. The rod is pivoted to the lever while the piston is disposed slidably in the large slot of the lid. The piston is provided peripherally with a circular groove in which a sealing ring is received.