The present invention relates to a circuit board. A circuit board in accordance with an embodiment of the present invention includes a base substrate; an interlayer insulating layer covering the base substrate; a via structure passing through at least the interlayer insulating layer of the base substrate and the interlayer insulating layer in the vertical direction; and an etch stop pattern disposed on the interlayer insulating layer in the horizontal direction to surround the via structure and made of an insulating material.