The plasma decomposition of gaseous dodecane has been investigated in a non-thermal BaTiO3 packed-bed plasma reactor in the atmospheric pressure streams of N-2-O-2 mixtures using FTIR and OES spectroscopy. Results suggest that energy transfer reactions of the electronically-excited nitrogen metastable, N-2(A), with dodecane play an important role in the initiation steps that lead to the dissociation of C-H and C-C bonds at the different positions. Increasing the percentage of oxygen in the nitrogen (up to 40 %) does not increase the dodecane decomposition, as metastable nitrogen reacts with the additional oxygen to create increasing NO and NO2 instead. N2O formation does not change significantly with increasing oxygen concentration but this is strongly correlated to the oxygen lattice in the BaTiO3 pellets used in the reactor. The maximum degradation efficiency found was to be similar to 21 % with an energy efficiency of 2.63 mg kJ(-1).