An integrated magnetic device disposed on a system circuit board is disclosed. The integrated magnetic device comprises a first magnetic device and a second magnetic device. The first magnetic device comprises a primary winding having at least a terminal; a secondary winding disposed corresponding to the primary winding, a magnetic core assembly assembled with the primary and secondary windings and partially covered by the primary and secondary windings, and a receiving chamber. The second magnetic device has a central through hole and a plurality of conductive ends. The second magnetic device is received in the receiving chamber of the first magnetic device and electrically connected to the system circuit board via the conductive ends, and the terminal of the primary winding of the first magnetic device pierces through the central through hole of the second magnetic device and electrically connects to the system circuit board.