The invention provides a device for processing a bevel edge on the edge of an airplane plate. The device comprises a plate clamping device, a pneumatic file fixing device, an angle adjusting device and a pneumatic file position adjusting device, wherein the plate clamping device is used for horizontally clamping and fixing a plate, the bevel edge of which is to be processed; the pneumatic file fixing device is used for fixing a pneumatic file; the angle adjusting device is connected with the pneumatic file fixing device and is used for adjusting the angle of the pneumatic file; the pneumatic file position adjusting device is connected with the angle adjusting device and is used for driving the pneumatic file to be adjusted in the left-right direction and the front-back direction. The device has the beneficial effects that when edge cutting needs to be carried out on the plate, the pneumatic file is fixed firmly by the pneumatic file fixing device, the plate is horizontally clamped by the plate clamping device, then the pneumatic file is adjusted to a position at a proper angle by the angle adjusting device, so that the angle of the bevel edge on the edge, processed by the pneumatic file, of the plate is consistent with the requirement, and finally the pneumatic file is driven by the pneumatic file position adjusting device to firstly move forward to come into contact with the edge of the plate and then move horizontally, thus achieving completion of plate edge processing.