Structure investigation results for MASHS powder Fe40Al/Al2O3 are presented. The powder structure formation proceeds via two stages. On the first step (mechanical activation) aluminothermal reaction takes plays in the system Fe+Al+Fe2O3, leading to formation of nanocomposite precursor Fe-Al-Al2O3. On the second step (SHS), iron and aluminum reacts, forming intermetallic FeAl. As-synthesized composite powder completely inherits the precursor structural morphology in spite of the phase transformations taking place during the production process. Such a production route provides the formation of intergrowth nanocomposite material structure with improved interfacial strength.