Oxidation of magnesium in mixtures NaClO4 + Mg + metal oxide or peroxide has been investigated using differential thermal analysis (DTA). In the systems with peroxides Na2O2, Li2O2, BaO2, CaO2 or ZnO, magnesium oxidizes simultaneously with decomposition of NaClO4 in the region 380–520°C, which is 100–200°C below the oxidation temperature of magnesium in air. In the ternary systems with transition-metal oxides NiO, CuO, FeO, and Fe2O3, magnesium transforms into oxide at above 600°C after sodium perchlorate had been decomposed completely. The low-temperature oxidation of magnesium occurs in the systems in which sodium chlorate is accumulated during the catalytic decomposition of NaClO4. Original Russian Text © V.D. Sasnovskaya, A.P. Razumova, 2006, published in Zhurnal Neorganicheskoi Khimii, 2006, Vol. 51, No. 9, pp. 1439–1444.