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The oxidation of small alkanes by the vanadium oxide cation VO2⁺ in the gas phase has been studied by Fourier transform ion-cyclotron resonance mass spectrometry (FTICR-MS). Sophisticated mass spectrometric experiments in conjunction with investigation of deuterium-labeled substances are used to elucidate the mechanistic details of the reactions. In marked contrast to oxidative dehydrogenation followed by elimination of ethene in the reaction of VO2⁺ with ethane, the corresponding reaction with propane mainly affords elimination of dihydrogen concomitant with an ionic product assigned to the allyl complex (η³-C3H5)V(O)(OH)⁺. In the case of n-butane/VO2⁺, a combined loss of H2 and H2O provides yet another product channel. Branching ratios, reaction rates, and some mechanistic aspects of the oxidation of propane, n-butane, and isobutane by VO2⁺ are reported. The experiments are complemented by a computational study of the potential energy surface of propane/VO2⁺ by means of density functional theory.