Аннотация:An approach to the description of the structure of a typical background magnetic field, generated by stochastic flow of a conducting fluid, is proposed which is based on the use of a magnetic field direction correlator. The difference between this correlator and the traditionally used magnetic field correlator describing abrupt peaks in the alternating structure of a magnetic field is discussed. An evolution equation for the direction correlator is derived in the short-wave approximation and solved asymptotically in the limit of large magnetic Reynolds numbers.