In order to investigate the effect of electric field formed by charged capillary on electrostatic atomization process, an electrostatic atomization system which was suitable for a single or double capillary was designed. Based on the electrostatic atomization system, a study on the atomization mode with ethanol was experimented, and the electro-spraying images were continuously recorded in memory by using high-speed camera. The dripping mode, spindle mode, oscillating-jet mode, precession mode, cone jet mode and multi-jet mode were obtained by systematically analyzing plenty of electrostatic atomization pictures. Under the experimental condition of the cone jet mode, based on the superposition principle of electric field and elliptic integral method, electric field of the single and double capillary electrode space was carried out by theoretical analysis and numerical calculation. The research results showed that electric field strength along the axis of capillary electrode reached its maximum value. The electric field was decreased with the decrease of φ and r, which represented the angle of point P to capillary axis in positive direction and the distance between points of O and P. Compared with single capillary under the same conditions, the electric field strength between the two capillaries along radial direction was decreased, while it was increased along axial direction. The angle between electric field and jet axis was from -9° to -2°. The electric field formed by the double capillary electrode was symmetrical with respect to x=0.5h plane, and the electric field intensity generated around each capillary was opposite in the x direction. Due to the characteristics of the electric field produced by two capillaries, the droplets formed by electrostatic atomization were deviated from the geometrical symmetry of the capillary.