The magnetic and structural properties of the FexMn0.95–xAl0.05 (0.40 ≤ x ≤ 0.50) alloy system prepared by mechanical alloying during 12, 24, 36 and 48 hours, were studied by Mössbauer spectroscopy and X-ray diffraction. By X-ray it was proved that the lattice parameter is nearly constant (≈︂3.64 Å) with the milling time and composition. All the diffractograms exhibit the f.c.c. phase characteristic peaks, except for the 12 hours milling samples which present additional Fe, Mn and Al peaks. Then for this time the alloys were not consolidated. Also, it was proved that the mean grain size increases between 12 and 24 hours milling and then decreases for 36 and 48 hours. This decrease is attributed to the breaking of the grains. The Mössbauer spectra of the 12 hours milling samples were fitted with a hyperfine field distribution and a sextet, corresponding to the f.c.c. alloy and the Fe, respectively. From the fits of the spectra it was obtained that the mean hyperfine field decreases from 2.7 to 2.2 T when the Fe content increases from 40 to 50% for the 12 hours milling samples and it remains nearly constant with the Fe content (≈︂2.9 T) for 24, 36 and 48 hours milling samples.