The luminescence spectra of a series of CdTe|Cd0.7Mg0.3Te heterostructures with a single quantum well are studied in wide ranges of the optical excitation level and temperature. The change in the luminescence spectra corresponding to the transformation of an exciton gas into an electron-hole plasma is traced. When luminescence was excited by a light strip on the sample surface, stimulated electron-hole plasma emission is polarized perpendicular to the strip. Keywords: II-VI quantum well structures, luminescence, high excitation, exciton, electron-hole plasma.