The magnetic fixing comprises two parts. The first, which is fixed on the ski (2), is constituted from a magnetised element (3) and has an indentation (4). The second is fixed under the sole (1) and is constituted from a magnetic element (6) and has a projection (7) which fits in the first indentation. The two parts stay fixed together through magnetic attraction and additionally by interlocking of the projection in the indentation.Each part is fixed on its support by an interface plate (15) by screws (16). The magnetic dipoles of each magnetic element are organised in sectors where the magnetic fields are either in identical directions or alternatively in different directions. A rotational or translational movement of one part of the system relative to the other makes coincident the two magnetic fields from different directions.