Abstract: To obtain the electrostatic field property of an aerial target,the main factors influencing the plane's electrostatic field are analyzed,including the free electron,positive ion or negative ion,and the soot carbon particles in the jet firebox.Mathematical model of the jet firebox is established,the firebox charging properties are analyzed with the help of simulation.The results indicate that the key factor which influences the charging property of jet firebox is the soot carbon particle,and the particle diameter and its charge quantity influence the charge quantity and polarity of the jet firebox.This provides a basis for further research on charges upon jet fuselage cover.