Electron paramagnetic resonance spectra of NO species in Ti–Sb oxide catalysts containing < 3 mol. % Sb₂O₅ (thermal treatment at T>770 K) have been studied. NO is formed as a result of oxidation of an admixture of NH₃ in TiO₂ matrix. Signals of I and II types with g=2.002, A⁾=32 Гс, g=1.914, g=1.943 are conditioned by NO molecules in π-form of stabilization. At oxidation the signal of ²unusual² NO with g_x,y=2.013, g_z=1.957, A_x=18 Гс parameters was found by us. These parameters can be explained in a model of σ-stabilization of this rate.