A coreless thin substrate with embedded circuits in dielectric layers is provided. The substrate includes a plurality of first patterned dielectric layers with embedded circuits, and at least a second patterned dielectric layer with embedded conducting elements. The second patterned dielectric layer is disposed between the first patterned dielectric layers, such that the embedded conducting elements electrically conduct the circuits of the first patterned dielectric layers through thermal lamination. Thus, a conventional through-hole formation process after the thermal lamination is skipped, and the substrate has a thinner and flatter profile. In one embodiment, the first patterned dielectric layers are inkjet printed layers with negative images. Moreover, the embedded circuits are flush with and exposed from an upper surface and a lower surface of the corresponding first dielectric layers.