Abstract: An arrangement for locking a nut on a spindle, e.g. for fixing roller bearings on wheel axles, comprising a lock washer with an axial pin, a lock plate and a lock ring. The lock plate has an opening with twelve corners in which a non-rotatable nut has thirteen depressions for the axial pin. The lock washer is disposed non-rotatable on the spindle, and for this purpose it can have an approximately polygonal opening for an axle portion of corresponding cross section. When the lock plate surrounds the nut and the axial pin projects into one of the depressions, the nut is fixed against turning. The lock plate is held in place by the lock ring which lies in a groove in the nut.