A method for manufacturing a circuit substrate comprises the following steps of: firstly, forming a medium layer on at least one surface of a substrate and forming an insulating layer on the medium layer; then, removing a part of the insulating layer and a part of the medium layer so as to form at least one blind hole in the medium layer and in the insulating layer; forming a chemical plating layer on the inner wall of the blind hole and on the un-removed insulating layer, wherein the bonding force between the insulating layer and the chemical plating layer is stronger than that between the medium layer and the chemical plating layer; and finally, electroplating a patterned conductive layer so as to cover the chemical plating layer.