Printed circuit board and preparation method thereof

The invention discloses a printed circuit board and a preparation method thereof, and the preparation method of the printed circuit board comprises the steps: obtaining a substrate; a double-sided bonding layer is bonded to a preset position of at least one surface of the substrate, a through hole is correspondingly prepared in the dielectric layer based on the preset position, and the thickness of the double-sided bonding layer is the same as that of the dielectric layer; covering at least one surface of the substrate with a dielectric layer so as to enable the double-sided bonding layer to be accommodated in the through hole; covering one side, far away from the substrate, of the dielectric layer with a conductive layer for lamination to obtain a laminated plate; processing the laminated board, removing the double-sided bonding layer and the conductive layer at the preset position of the processed laminated board, and exposing the preset position of the substrate to obtain the printed circuit board; through