Plasma modification is an effective way to improve the catalytic activities of materials.Firstly,Co₂(OH)₂CO₃ precursor was synthesized by a hydrothermal method.Then,the precursor was subjected to the oxygen atmosphere low?temperature plasma, and the surface modified Co₃O₄ catalyst (Co₃O₄?P) was obtained,which was further characterized the XRD,SEM,H₂?TPR,O₂?TPD,TEM,XPS,FTIR,Raman spectrum and UV?visible spectrum.The results demonstrate that plasma treatment could reduce the average valence state of Co elements in Co₃O₄ to form more defective sites on the catalyst surface,and lower the Co-O bond energy of Co₃O₄ to improve its low temperature reduction performance.Under the irradiation of full solar spectrum light with intensity of 776 mW/cm²,reaction space velocity of 30 000 mL/（g·h）and toluene concentration of 500 μg/g，the toluene degradation performance of the Co₃O₄?P catalyst could reach 100.0%，which was approximately twice that of the Co₃O₄ catalyst (Co₃O₄?T) prepared by thermal calcination.