A magnetic -field-sensitive sensor arrangement comprises - a first conductor arrangement with at least two electrical half-bridges each having at least two bridge branches, at least one of which contains a magnetic-field-sensitive semiconductor element, which sensor arrangement supplies a measurement signal depending on the magnetic field strength of a component of a magnetic field at the location of at least one of the half-bridges, this being referred to as the measurement field and being aligned in a measurement direction of the sensor arrangement, and - a device which forms the measurement field with a value of its magnetic field strength, which depends on the magnetic permeability of a medium that at least partially surrounds the sensor arrangement, whereby the measurement signal is a measure of the magnetic permeability of the medium. A simple sensor arrangement for measuring a medium which affects a magnetic field is thus provided.