Fe films have been grown on cubic GaN(001) layers by molecular beam epitaxy. They were studied in situ by reflection high-energy electron diffraction. X-ray photoemission spectroscopy and X-ray photoelectron diffraction and ex situ by Rutherford backscattering spectrometry (RBS). X-ray diffraction and alternating gradient field magnetometry. Despite the large lattice mismatch between Fe and cubic GaN [Deltaa/a = (2a(Fc) - a(GaN))/a(GaN) = +26%], the growth of Fe on GaN was found to be epitaxial with the orientation relationship (001)[100]Fe\\(001)[110]GaN i.e. with a 45 rotation of the Fe unit cell with respect to the GaN one. The mosaic spread of the Fe film does not exceed 1. In such conditions we observed that the magnetic hysteresis loops show a cubic anisotropy with the easy axes along <100 >, as for bulk bee Fe. (C) 2002 Elsevier Science B. V. All rights reserved.