A connection structure of a circuit board is disclosed. In one aspect, the connection structure includes a first circuit board, a second circuit board and an adhesive member. A first connection pad and a second connection pad are disposed on the first circuit board. The second circuit board has a first surface facing the first circuit board. A plurality of third connection pads and fourth connection pads are disposed on the first surface of the second circuit board in a staggered pattern. The adhesive member is disposed between the first and second circuit boards. At least one of the third and fourth connection pads is electrically connected to a wire which is disposed on a second surface of the second circuit board opposite to the first surface of the second circuit board.