Rezumat
On the basis of the analysis of the dispersion equation for nonaxisymmetric capillary waves on a surface of cylindrical jet ideal incompressible conductive liquids moving collinear to a uniform electrostatic field in a material environment medium, is shown, that increasing of an environment medium density carries destabilizing character. The instability of a nonaxisymmetric waves has threshold character on speed of a jet relative to medium.