The influence of grinding on the structure and catalytic performances of two families of oxides, namely the perovskite-type La 0 . 8 Sr 0 . 2 MnO 3 + /- λ and the spinel-type Li-Mn-O, was investigated. Ball-milling of the well-known La 0 . 8 Sr 0 . 2 MnO 3 + /- λ prepared either by a solid state reaction or by a sol-gel method led to (i) a decrease in carbon black combustion temperature of 100 o C (T C =540 o C) and of 40 o C (T C =505 o C) for ceramic and sol-gel ground 5-h samples, respectively, and (ii) to faster kinetics and higher rates of toluene conversion. A greater enhancement of the catalytic performances was obtained by using mechanical milled lithiated manganese oxides that are reported as promising catalyst candidates for the first time. Li-Mn-O catalysts were synthesized by room temperature mechanochemistry of a stoichiometric mixture of Li 2 O and MnO 2 using various milling times (0<t m i l l i n g <15 h). The nonstoichiometry, large surface area and disorder nature of the ground samples were of great benefit regarding catalytic applications. A remarkable decrease in the carbon black combustion temperature of 200 o C (from 650 to 450 o C) was obtained when using a mixture of Li 2 O and MnO 2 ground for 3 or 4 h. This low T C value favorably compares with the T C of 500 o C of ceramic LiMn 2 O 4 , which shows, however, better catalytic performances than most of the perovskite-type oxides. The grinding proves to be efficient as well for volatile organic compounds (VOCs) combustion. The inactive ceramic LiMn 2 O 4 exhibits a 100% toluene conversion rate for a temperature lower than 200 o C when ground 5 h.