The properties of vanadium pentoxide (V2O5) films deposited by reactive DC sputtering from vanadium target were investigated. In particular, the chemical state of elements and microstructure of films were analyzed by X-ray photoelectron spectroscopy, X-ray diffraction and field-emission scanning electron microscopy. The percentage of oxygen in the sputtering chamber affects the chemical state of vanadium in the film. Higher oxygen partial pressure makes to vanadium to be oxidized from V4+ to V5+， and the grain size increased with grain a shape of needles, but the content of oxygen with high binding energy decreases. Higher temperature of substrates causes the grains to grow from needles to large flakes lying parallel to the substrate, and vanadium is oxidized to the stable high binding energy states.