Surface absorbed oxygen (O_ads) and surface lattice oxygen (O_latt) specie are critical for accelerating oxidative removal of toluene over MnO₂-based catalyst. Herein, an excellent CuMnO₂ catalyst has been successfully designed and fabricated. Doping Cu²⁺ with strong Jahn-Taylor effect into the lattice of MnO₂ not only weakens the strength of Mn-O bonds but also induces the formation of oxygen defects, which enhances the reactivity of O_latt and promotes the adsorption of gaseous oxygen molecules. As a result, CuMnO₂ reaches 50 % and 90 % of toluene conversion at 212 and 241 °C respectively, showing obviously better catalytic performance compared to CeMnO₂, NiMnO₂, CoMnO₂ and δ-MnO₂. Moreover, CuMnO₂ exhibits outstanding stability, good cycling stability and excellent water resistance ability. The in situ DRIFTS demonstrate that ring opening of benzoate and the dehydrogenation of benzaldehyde are key processes that affect the deep oxidation of toluene.