The effect of small amounts of H2(0.005–1.0%) on the deionization processes in Ne‐A discharges was measured by microwave cavity techniques. At low charged particle densities the deionization of discharges produced in Ne‐A mixtures is determined by the ambipolar diffusion of electrons and molecular argon ions (A+2). The charged particle density in the deionization period following a pulsed discharge decays exponentially with time. For a discharge tube of 7 mm i.d. filled with Ne‐A mixtures at a pressure of  20 Torr, the deionization of the plasma occurs with a time constant of 1.3 ms. The presence of a small amount of H2(0.005%) enhances the deionization process drastically. The charged particle density decreases much more rapidly (time constant of 0.61 ms) than in the pure mixture. A similar increase in the deionization rate was measured in pure A. At low charge particle densities the deionization rate is determined by the ambipolar diffusion of a highly mobile hydrogen ion, possibly H+3, compared to relatively less mobile argon ions.