Substrate for electrical devices is disclosed. An embodiment for the substrate comprised of an insulator, a conductive element(s) and a conductive material(s), wherein the conductive element embedded in the insulator, and two surfaces of the conductive element exposed to two surfaces of the insulator for electrical connection respectively, wherein the upper surface of conductive element is below the upper surface of insulator and is plated by the conductive material, meanwhile the conductive element include a protruding portion which is protruded the insulator, in this manner, solder balls are not needed, moreover the conductive element can further include an extending portion; the present invention may be capable of affording a thinner electrical device thickness and enhanced reliability.