A multi-layered circuit board proofed against conductor loss or diminution when heated includes first and second circuit base boards. Each first circuit base board includes a first dielectric layer and a first wiring layer formed thereon and a first stepped paste block as a conductor formed in the first dielectric layer. The first stepped paste block is electrically connected to the first dielectric layer. Each second circuit base board includes a second dielectric layer and a second wiring layer, a second stepped paste block as a conductor is formed in the second dielectric layer. When pressed together for an electrical interconnection, the paste blocks are sealed and thus captive between the first and second circuit base boards.