A composite circuit board includes an insulation layer, an inner circuit layer, a first conductive layer and a second conductive layer embedded in the insulation layer, a third conductive layer and a fourth conductive layer formed on opposite surfaces of the insulation layer. The third conductive layer electrically connects with the first conductive layer. The fourth conductive layer electrically connects with the second conductive layer. The inner circuit layer is in a middle portion of the insulation layer. The first conductive layer and the second conductive layer respectively forms on opposite sides of the inner circuit layer. The insulation layer forms a plurality of first through holes between the first conductive layer and the inner circuit layer, a plurality of second through holes between the second conductive layer and the inner circuit layer.