The invention discloses an oxygen sensitive variable ink. The oxygen sensitive variable ink comprises the following components: an oxygen sensitive reactive dye, a reducing agent, a binder, a hydrophobic agent and an organic solvent. By adopting the binder of the variable ink, the film formation viscosity of the ink is increased; an ion binding is generated by the hydrophobic agent and the oxygen sensitive reactive dye, so that the oxygen sensitive reactive dye has a hydrophobic function; besides, the reducing agent of the variable ink can be substituted by a photocatalyst material and an electron donor material, and the variable ink is an UV activated variable ink; after being radiated by the UV light with proper wavelength, the oxygen sensitive reactive dye is re-activated by a photo electron generated by the photocatalyst material so that the oxygen sensitive reactive dye returns to a reducing state, and therefore, whether an oxidizing reaction is generated can be judged through the color change of the oxygen sensitive reactive dye in reducing state.