Maghemite nanoparticles (NPles) prepared by the radiation-chemical method (RCM) from alcoholic FeSO4 solution were annealed in air in the temperature range of 200–575 ºC and then coated with NPles silver precipitated from aqueous AgNO3 solution irradiated by pulsed electron beam with electron energy of 500 keV. NPles Ag altered the path of phase transformations of NPles maghemite in Ag-maghemite nanocomposites (hematite) compared to the phase transformations in NPles pure annealed maghemite. SEM and mapping showed a porous structure and uniform distribution of NPles Ag on the surface of NPles maghemite/magnetite in the composites. EDX and XPS showed the presence of small amounts of S and N impurities from precursors. Ag precipitation changed the shape of the PL spectra of maghemite - the spectra broadened and additional peaks appeared at λ = 454 nm from internal photoluminescence and surface plasmon resonance of Ag nanoparticles. An unstable aqueous suspension of NPles maghemite with the combined use of two dispersants (sodium citrate + Darvan-CN) was characterised by high sedimentation resistance. The degradation of methyl violet dye after 25 min of ultraviolet irradiation was 12 %.