Abstract: In view of the lack of systematic research on electro-atomization under the action of unsteady electric field in the existing literature, combined with the actual demand of the space engine for the pulse operation of the thruster, the experimental study on the oscillation behavior of the cone jet under the action of the unsteady electric field is carried out, using the high-speed camera which records the pulsating deformation process of the cone jet under the action of unsteady voltage disturbance. This paper discusses the matching relationship between the jet oscillation frequency and the voltage disturbance frequency, and analyzes the influence of different disturbance voltage parameters on the jet shape. Studies show that when the voltage disturbance frequency is in the low and high frequency range under the action of an unsteady electric field, the jet oscillation frequency is close to the voltage disturbance frequency, and the jet is in the oscillating cone jet mode; when the disturbance frequency is in the middle frequency range, the jet oscillation frequency is in the range of 300–500 Hz, and the jet is in the intermittent jet mode; as the amplitude of the unsteady disturbance voltage increases, the frequency range of the jet in the intermittent jet mode gets larger, and the range in the oscillating cone jet mode becomes smaller; The greater the voltage disturbance frequency is, the greater the cone jet angle of the jet in the oscillating cone jet mode is.