A plate separation assembly and an operating method thereof are used to disassemble a plurality of plates for a coreless process. The plate separation assembly includes a machine and a composite board consisting of the plurality of plates. The machine includes a frame, onto which a clam shell structure and a linkage mounted. The inner surfaces of the clam shell are perforated, leading into one air pump behind each surface. The plurality of plates are held together by separable interface layers. To disassembly, the composite board is placed in between the two clam shell surfaces. Turning on the air pumps will create a vacuum between each interface of the clam shell surface and the board surface. The linkage is used to open the clam shell by force which separates the plates.