Discharge parameters have been investigated experimentally and theoretically for a high‐pressure, ultraviolet‐preionized, transversely excited CO2laser. The theoretical model including the excitation circuitry is presented which predicts the discharge performance at pressure ranges of 2–10 atm in a satisfactory manner. The operatingE/Nand discharge impedance in a quasi‐steady field were studied by accurately measuring the voltage‐current waveforms;Eis the electric field strength andNthe gas number density. The electron transport coefficients have been found to be a function of the pressure versus the change of the measured voltage waveforms relating to that pressure. The theoretical results treating the transport coefficient as a function of the pressure were in very good agreement with the experimental results.