An EMI noise reduction board is disclosed. The electromagnetic interference (EMI) noise reduction board having an electromagnetic bandgap structure for shielding a noise includes: a first area having a ground layer and a power layer; a second area placed in a side portion of the first area having an electromagnetic bandgap structure therein. The electromagnetic bandgap structure includes: a plurality of first conductive plates and a plurality of second conductive plates placed on a same planar surface along the side portion of the first area; and a stitching via configured to electrically connect the first conductive plate to the second conductive plate through a planar surface that is different from the first conductive plate and the second conductive plate.