A flexible circuit board assembly for an LED lamp of the present disclosure comprises: a resin layer having a strip shape; a conductive signal line layer formed from a predetermined pattern provided on the upper part of the resin layer; and a radiation layer provided on the lower part of the resin layer, having a thickness relatively thicker than that of the conductive signal line layer, and radiating the heat generated from an LED mounted on the signal line layer, wherein the signal line layer and the radiation layer are made from one material from among copper, aluminum, copper alloy and an aluminum alloy.