An integrated magnetic device disposed on a system circuit board is disclosed. The integrated magnetic device comprises a bobbin, a magnetic core assembly, and a conductive structure. The bobbin has a main body for a primary winding to wind thereon and a channel piercing through the main body. The conductive structure comprises plural conductive units corresponded to each other and a first magnetic device. Each of the conductive units has a hollow portion, a receiving hole, and at least a conductive pin. The first magnetic device is electrically connected to the conductive units by the conducting part thereof piercing through the receiving holes of the conductive units. The conductive units are spaced by the main body of the bobbin, and the hollow portions of the conductive units are corresponded to the channel of the bobbin to receive parts of the magnetic core assembly, so as to assemble the bobbin, the magnetic core assembly and the conductive units as a second magnetic device. The first and second magnetic devices are integrated by the conductive structure and disposed on the system circuit board through the conductive pin of each of the conductive units of the conductive structure.