Abstract: Nitrogen oxides (NO_x), as the main pollutants of air pollution, do serious harm to the ecological environment and human health. SCR technology is widely used as the most effective method to deal with nitrogen oxides. The core of SCR technology lies in SCR catalyst. The reaction temperature of traditional commercial catalysts is difficult to reach the optimal operating temperature range, so expanding the temperature window of V₂O₅/TiO₂ catalysts to the low-temperature region while reducing vanadium loading is the key issue to be solved. A series of V₂O₅/TiO₂ catalysts with different vanadium precursors and different vanadium loadings were prepared by solid-phase synthesis method. The physicochemical properties of the catalyst were analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, temperature programmed removal of ammonia and temperature programmed reduction of hydrogen, and the denitrification activity of the catalyst was evaluated in a fixed bed reactor. The catalysts prepared using vanadyl oxalate (VOC₂O₄·xH₂O) and vanadyl acetylacetonate (VO(acac)₂) as vanadium precursors with a vanadium loading of 5% exhibited the highest denitrification activity with a stable NO_x conversion of 100% in 200−350 ℃. Compared with the catalysts prepared using ammonium metavanadate (NH₄VO₃) and vanadyl sulfate (VOSO₄·xH₂O) as the vanadium precursors, the maximum activity temperature of VOC₂O₄-V5Ti and VO(acac)₂-V5Ti migrated to the low-temperature region by about 150 ℃. The denitrification activity of a low vanadium content (1%) catalyst prepared using VO(acac)₂ precursor was even higher than that of a high vanadium content (6%) catalyst prepared using NH₄VO₃ precursor. The VOC₂O₄ and VO(acac)₂ vanadium precursors could effectively regulate the active sites and polymeric states on the catalysts with a high V⁴⁺/V ratio and promote the interaction of V atoms with different valence states. Furthermore, this study also provided an effective method for the preparation of low-vanadium and high-activity denitrification catalysts at low temperatures.