Identification of gas impurities in helium by selective registration of groups of fast electrons created in Penning ionization of impurities atoms or molecules by metastable helium atoms at pressures of 7–40 Torr is realized. The collisional electron spectroscopy (CES) method is applied and is experimentally verified. Identification of impurities atoms and molecules is accomplished in collisional regime of movement of the particles, where the different groups of electrons have no time to relax in energy by collisions in the volume and behave independently of each other. An original design of microplasma gas analyzer is proposed, containing only nonlocal negative glow plasma of a short dc microdischarge. Registration of the energy spectra of penning electrons by means of an additional electrode-sensor, located at the boundary of the discharge volume is performed. The sensor has large collecting area compared to classical Langmuir probes, contributing to significant enhancement in the measurements sensitivity.