To provide a magnetron sputtering apparatus which can improve the plasma density in a relatively easy manner without using any high frequency power source circuit which is expensive and requires a space for a matcher.

In the magnetron sputtering apparatus in which a substrate and a substrate-facing cathode facing the substrate are provided, a center magnet and peripheral magnets surrounding the center magnet are disposed on a back side of the substrate-facing cathode so as to generate an erosion area on a face side of the substrate-facing cathode, sputtering is performed by the plasma generated in the erosion area, and generated sputtering particles are allowed to reach the substrate to perform the sputtering film deposition, peripheral cathodes are disposed around the face side of the substrate-facing cathode, and a reinforcing magnet is disposed on the back side of the peripheral cathode so that the pole opposite to the pole of the center magnet is directed to the center side of the substrate-facing cathode.