AbstractIn this study, highly‐dispersed perovskite‐type oxides LaMnxCo1‐xO3 supported on mesoporous SiO2 (LMxC1‐xO/SiO2) were synthesized by a citric acid‐assisted deposition method. For LMxC1‐xO/SiO2 catalysts, the double B‐site transition metal ions can not only significantly arise the surface defects, but also lead to the formation of (Mn3++Co3+)/(Co2++Mn4+) redox cycle, both of which were able to improve the catalytic performance of LMxC1‐xO/SiO2 in n‐butylamine combustion. Strikingly, LM0.2C0.8O/SiO2 catalyst showed the optimum catalytic performance (T90%=210 °C at a space velocity of 15,000 mL gcat−1 h−1) and the lowest NOx yield among the LMxC1‐xO/SiO2 samples, which could be greatly assigned to the accelerated activation and circulation of the oxygen species initiated by the surface defects and redox cycle.