Abstract: Capillary discharge based pulsed plasma thrusters have great prospects in the application of micro-nano satellites in orbit maneuvering.This paper systematically studied the influence of different propellant materials on the thruster’s discharge characteristics,energy deposition process,ablation characteristics,output thrust parameters and plasma plume pa-ra-meters.The experimental results indicate that propellant materials have little influence on the energy deposition process,and the difference in ablation flux of different propellant materials is small.However,due to the large differences in the rela-tive molecular mass of the decomposition components of different materials,the plasma electrothermal acceleration process is affected,which in turn affects the thrust characteristics of the thruster.ETFE and PTFE has high impulse bit and thrust to power-to-power ratio,ETFE has better uniformity in output parameters,UPE and POM could achieve high specific impulse.