A three-dimensional instability analysis of an electrified non-Newtonian liquid jet is performed in this paper so as to understand the competition between viscoelastic stresses, electric force, and surface tension. The analysis employs the leaky-dielectric model to account for the charge transport process and the Oldroyd-B model to take the viscoelastic effect into account. Results show that the viscoelastic stresses play a stabilizing role while electrification destabilizes the disturbances with shorter wavelength and higher azimuthal wave numbers. However, the viscoelastic stabilizing effect is not so significant on the sinuous mode (with azimuthal wave number m = 1) compared with the other modes, which thus promotes sinuous disturbances. This result is consistent with the presence of bending motion in most experimental observations.