Abstract: In order to solve the problem of the difficulty of igniting and steadily propagating a continuous rotating detonation engine when using liquid hydrocarbon fuel, an experiment was carried out using a dielectric barrier discharge excited by a nanosecond power supply to crack n-decane, the single alternative fuel to aviation kerosene, in a pre-heated argon environment. By changing the voltages and the discharge frequencies, the concentrations of different components as well as a number of different species were acquired. The generating mechanism of olefins and alkanes together with their competition mechanism were acquired. The influence of the voltage on isomer products was also analyzed. The results demonstrate that the bond energy distribution and the species generating condition are the main factors affecting the formation of the products. With the increasing of voltage and discharge frequency, small molecule olefins, large molecular olefins, large molecular alkanes, small molecular alkanes, and hydrogen were detected, and in turn, their concentrations were also increased except for ethylene; what is more, when the voltage was increased over 8.5 kV, the n-butene converted to trans-butene, and the n-pentene converted to isoamylene.