Polarized light emission from polymer light emitting diodes (LEDs) is one step towards improved sources of background illumination for efficient liquid crystal displays. It is demonstrated that the fabrication of organic LEDs based on poly(p-phenylene)s by the Langmuir-Blodgett technique enables the polarization of the emitted light to be controlled. The ratio of the intensity of light polarized parallel and perpendicular to the dipping direction is the highest reported so far. Photoluminescence and electroluminescence spectra are presented and discussed.