Transition metal oxide MnOx shows great potential in catalytic formaldehyde (HCHO) pollution degradation at room temperature, but it is difficult to effectively overcome the catalyst deactivation caused by the accumulation of intermediates. Hereon, a 3D conductive aerogel catalyst with cellulose nanofibers (CNF) skeleton supported MnOx nanoflowers and carbon black (CB) was prepared by freeze-drying. Based on the aerogel catalyst (MnOx/CB/CNF), an electro-injection-enhanced catalytic oxidation (EICO) strategy was proposed for HCHO degradation by promoting the formation lattice oxygen and reactive oxygen species O* . In the dynamic test (∼15 ppm at the weight hourly space velocity (WHSV) of 600000 mL/gMnOx·h), the HCHO-to-CO2 conversion efficiency of MnOx/CB/CNF by electro-injection can be enhanced to 76.27%, which is 26.4% higher than that without electro-injection, and the corresponding dynamic efficiency did not show a decreasing trend within 72 h. This proposed EICO strategy may realize the efficient and long-term pollutant degradation at room temperature.