The transverse non-specular magneto-optical Kerr effect was measured in diffraction from an inhomogeneous grating made of ferromagnetic Fe 0 . 7 5 Si 0 . 2 5 wires on a silicon substrate. The relative change in intensity of the diffracted beams when magnetisation is reversed (ΔI/I) n shows a large enhancement (from 1.8 10 - 2 up to 3 10 - 1 ) for angles of incidence corresponding to minima of I n . The relative magnetic response, ΔD n , where D n is the diffraction efficiency (I n /I i n c ), reaches maximum values for non-zero diffracted orders and is higher than that obtained in specular conditions.