We numerically investigate electrically driven polarized light emission from metal–insulator–metal (MIM) tunnel junctions based on inelastic electron tunneling (IET). The device comprises an Ag–SiO2–Ag stack, where the top electrode is patterned into subwavelength nanoantennas to tailor the polarization state of the emitted light. Linearly polarized emission is achieved using paired rectangular nanoslit antennas, oriented to define the polarization axis. Full-wave simulations reveal a degree of linear polarization (DoLP) of 100%, indicating pure x-or y-polarized emission depending on the slot configuration. Circularly polarized light is obtained by employing a z-shaped chiral nanoantenna, yielding a degree of circular polarization (DoCP) of 0.35 at the resonance wavelength. Stokes parameters calculated from absorption cross-sections and dipole-based emission models confirm the strong polarization control enabled by nanoantenna geometry. These results demonstrate a compact, electrically driven platform for polarization-selective light generation, offering a viable route toward integrated, tunable polarization sources in nanophotonic and optoelectronic systems.