Radioluminescence from electron-irradiated polyethylene doped with pyrene was investigated in the temperature range of 77-273 K. The spectra of emitted light were recorded, and temperature dependences of radioluminescence intensities at chosen wavelengths were examined using a wavelength-selected radiothermoluminescence technique. The experimental results were explained in terms of an electron-solute radical cation and solute radical ions recombination. Pyrene excimer emission was observed in the glass transition temperature range of the polyethylene matrix.