To provide a magnetic coupling element, capable of stably effecting high-speed communication by reducing the affection of external noise.

When an external magnetic field (external noise) exists, equivalent noise component is generated in both of a receiving coil 4 and a dummy coil 5 while respective noise components from the receiving coil 4, and the dummy coil 5 are offset each other in a differential amplifier 14. Only a signal component generated by the magnetic field of a transmission coil 3 is applied on a comparator 15 through a differential amplifier 14, to change the same here into a binary signal and output the same further through an output control circuit 18 and respective transistors 16, 17.