Abstract: The influence of low voltage electrode holes on the ignition initiating in same discharge volume was studied for the low temperature plasma ignition initiating of pulse detonation engine. Taking propane as fuel, air and pure oxygen as oxidant, fully considering the detail chemical reaction kinetics mechanism, having the low temperature plasma discharge area equivalent to high temperature and high pressure fire nuclear, a numerical simulation was implemented on the ignition initiating process about different low voltage electrode holes number and the diameter of the five kinds of igniters structure with Fluent software. The results show that, the more of the low voltage electrode holes and the large diameter will make the initial stage pressure and the temperature of discharge drop quickly. The axial initial flame volume of the detonation tube decreases with increasing of low voltage electrode holes area, and also cases the flame propagation speed slower, detonation wave peak pressure increase slowly, DDT time greatly increase. The smaller of low voltage electrode holes area, the more conducive to trigger the detonation. So the PDE of multi-cycle work needs reasonable low voltage electrode holes number and diameter to obtain good ignition initiating properties.