The invention relates to a file filling device which comprises an opening and closing mechanism and a pushing mechanism, the opening and closing mechanism comprises a first adsorption part, a second adsorption part, a sealing cover adsorption part, a first moving part and a first rotating part, and the first adsorption part is used for adsorbing or releasing a first surface of a sealing cover; the second adsorption part is arranged on the first moving part and used for adsorbing or releasing the second surface of the sealing sleeve, the first moving part can drive the second adsorption part to be close to or away from the second surface, the sealing cover adsorption part is arranged on the first rotating part and used for adsorbing or releasing the sealing cover, and the first rotating part can drive the second adsorption part to rotate around the rotating axis of the sealing cover; the pushing mechanism is used for containing files and can enter and exit from the envelope. Compared with the prior art, the file filling device does not depend on manual work of workers, the filling efficiency is high, and the labor cost can be reduced.