The particle dispersion level f/r in reactive spray deposited Al-Mg-Mn alloys, which was believed to control the statically recrystallized microstructure, was varied by changing the processing parameters, superheat temperature (ST) and atomization gas oxygen content, and along with small additions of Zr. Following simplified thc thermomechanical processing (TMP), fine microstructures with grain size 6.9 mm and stabilized subgrain structures with subgrain size about 1mm were achieved, which are believed to be suitable for improved superplastic deformation (SPD).