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Vanadium−cerium oxide catalysts, with different V/Ce atomic ratios, were prepared using vanadyl oxalate (VOC₂O₄) impregnated on ceria (CeO₂) as precursors. Subsequently, the freshly prepared solids were calcined under a flow of dried air at different temperatures from 400 to 800 °C. These solids have been characterized with different techniques: Raman spectroscopy, thermal analysis (TG-DSC), specific area measurements (BET), EPR, and solid-state ⁵¹V MAS NMR. Different vanadium species in the vanadium−cerium oxide catalysts have been evidenced. Polymeric V−O−V chains, vanadium tetrahedral surface species, and V₂O₅ phase are stabilized mainly when solids are calcined in the temperature range 400−500 °C. Their formation also depends on the vanadium content. For higher calcinations temperatures (≥500°C), CeO₂ reacts with vanadium (V) species to form a CeVO₄ mixed phase. Further to …