Disclosed are an electromagnetic bandgap structure and a printed circuit board that can solve a mixed signal problem between an analog circuit and a digital circuit. The electromagnetic bandgap structure in which a first metal layer, a first dielectric layer, a second dielectric layer and a second metal layer are stacked can include a first metal plate, formed between the first dielectric layer and the second dielectric layer; a second metal plate, formed on a same planar surface as the first metal plate, accommodated into a hole which is formed in the first metal plate and electrically connected to the first metal plate through a metal line; and a via, connecting the second metal plate to any one of the first metal layer and the second metal layer. With the present invention, the electromagnetic bandgap structure can be not only miniaturized but also have a low bandgap frequency.