Abstract: A vacuum processing device has at least one vacuum processing unit, which includes a housing defining a vacuum chamber, and a gate valve assembly. The valve assembly includes a lid plate. for covering an opening in the housing, and a connecting member connected fixedly to a rotating shaft. Each of several aligned adjustment rods connects the plate to the connecting member, and is disposed perpendicular to the plate. A plurality of resilientunits biases the plate away from the connecting member to press against a wall of the housing, which defines the opening. A plurality of adjusting units are movable respectively on the rods to vary the distance between a portion of the plate and a portion of the connecting member, which are interconnected by the respective one of the rods, so that the plate can be pressed entirely against the wall of the housing.