To enable power supply coupler and a vehicle-mounted coupler to be coupled and separated easily, when a battery of an electric vehicle is charged with high frequency power generated by magnetic coupling these two couplers and form these couplers in such shapes that they hardly become dirty and can be easily cleaned.

A power supply coupler 1 is constituted of a primary coil 3 connected to a power supply equipment, an outside yoke 4 which forms a magnetic path outside the coil 3, and a cylindrical mold 6 having a bottom which covers the coil 3 and the yoke 4. Meanwhile, a vehicle-mounted coupler 2 is constituted of a substrate yoke 8 which forms a closed magnetic path together with the yoke 4, a column-like core 9 formed upright on the yoke 8, a secondary coil 10 wound around the core 9, and a mold 11 which covers the yoke 8, the core 9 and the coil 10. The core 9 and the coil 10 are freely removably inserted into a hollow section of the coil 3, and the yokes 8 and 4 form a closed magnetic path.