A method for manufacturing a magnetic element is provided, comprising: forming a first accommodating slot, which holds the first sub-substrate, in the first assembly, to form a first wiring region including a first conductive layer and a second conductive layer; forming a first dielectric layer on an upper surface of the first assembly, and forming a second dielectric layer on a lower surface of the first assembly, wherein the first dielectric layer, the second dielectric layer and the first assembly form a second assembly; exposing lower end surfaces of the first conductive layer and the second conductive layer; and forming a third conductive layer on a lower surface of the second assembly, wherein one end of a first trace portion of the third conductive layer is in direct contact with and connected to the first conductive layer, to form a part of windings of the magnetic element.