Based on the models of charged liquid jets and Lagrange equation under the generalized coordinate, the dispersion equations of inviscid liquid jets in an electrostatic field were established and solved by using the numerical methods. According to analyzing the calculated values, the effects of different factors on axisymmetric models and non-axisymmetric models of charged liquid jets were studied. The results showed as follows. The maximum value of the disturbed growth rate of charged liquid jets is increased with the stronger electric field intensity. When the voltage is lower, the electrostatic field has a significant effect on the axisymmetric instability models. The non-axisymmetric instability models exert a dominant influence since the voltage is enhanced gradually in an electrostatic field and it leads the droplets to break up finally. Instability of charged liquid jets is increased as the jet radius reduces. The changes of the jet radius in the non-axisymmetric modles have more effects on the instability of charged liquid jets than in the axisymmetric models. The effects of different liquid dielectrics on the non-axisymmetric charged liquid jets instability become very obvious.