Provided are a circuit board and a method of manufacturing the same. The method includes: forming a pad portion and a lead line portion of a metal on an insulating substrate, wherein the lead line portion is connected to the pad portion; forming a conductive layer on the pad portion and the lead line portion, wherein the conductive layer has an upper surface comprising gold; forming an etching mask on the conductive layer so as to expose a portion corresponding to the lead line portion in the conductive layer; etching a portion of the lead line portion exposed by the etching mask and a portion of the conductive layer corresponding to the lead line portion using an etching solution containing an acid; and removing the etching mask.