Thin polycrystalline NiFe2O4 films in the thickness range 0.1–0.7 μm were prepared by subsequent oxidation of a metallic film deposited under vacuum. The experimental requirements to obtain a stoichiometric single-phase ferrite film are described in detail. The influence of preparation parameters on crystallographic and magnetic properties is extensively studied. It is shown that when the sintering temperature is increased from 930 to 1130°C, the film density increases and the grain growth occurs. During the grain growth a |111| fiber texture is formed and a surface roughness is created. The formation of the |111| fiber texture which is more pronounced for higher sintering temperatures is explained in terms of surface energy. It is shown that the magnetic properties measured by ferromagnetic resonance are determined by the density and microstructure of the thin film, but the surface roughness has no marked effect on the position and linewidth of the main resonance mode. The thermally induced strains are much lower than predicted by calculation, and this observation is explained by grain boundary cracks. The relevance of this study for the epitaxy of thin ferrite films is pointed out.