A multi-layer wiring structure includes a first conductive structure, a second conductive structure and an insulating layer. To manufacturing the multi-layer wiring structure, a first conductive structure and a second conductive structure are provided. The first conductive structure and the second conductive structure include a plurality of wiring patterns. Then, the insulating layer is disposed between the first conductive structure and the second conductive structure. The insulting layer is thinner than the first conductive structure or the second conductive structure. The first conductive structure, the insulating layer and the second conductive structure are laminated to form the multi-layer wiring structure. A planar magnetic element having a compact coil manufactured by the method is also provided.