Abstract: An E-shaped core is composed of a main core and side cores which are combined into one piece. A coil is wound around a bobbin which is inserted in the main core. A plate-shaped auxiliary core is connected to a sliding member. Connecting the E-shaped core and the auxiliary core completes the assembly of the magnetic head for a magneto-optical recording device. The auxiliary core surrounds the main core; therefore, the concentration of the magnetic flux at the end of the main core can be enhanced and the efficiency for generating magnetic field for a recording medium can be improved. In addition, the use of the E-shaped core and the plate-shaped auxiliary core permits easier machining of the cores.