As a multi-layered board, an EMI noise reduction board, having an electromagnetic bandgap structure with band stop frequency properties inserted into an inner portion of the board, includes a first area, in which a ground layer and a power layer are formed, and a second area, placed on a side surface of the first area, in which it has the electromagnetic bandgap structure formed therein so as to shield an EMI noise radiated to the outside through the side surface of the first area. The electromagnetic bandgap structure includes a plurality of first conductive plates, placed along the edge of the board, a plurality of second conductive plates, disposed on a planar surface that is different from the first conductive plates such that the second conductive plates are alternately disposed with the first conductive plates, and a via, which connects the first conductive plates to the second conductive plates.