A comprehensive physico-chemical characterization is carried out and the reduction kinetic and activity are studied of samples of CA-1-type catalyst for ammonia synthesis regenerated in quasi-equilibrium electric-arc low-temperature plasma. The experimental conditions are described for the plasma-chemical regeneration of a spent catalyst for ammonia synthesis. The samples regenerated are characterized by means of determining: the specific surface (using the Klyatchko-Gurvich technique); the size of the finely-dispersed particles (electron microscope analysis): and the phase content (X-ray phase analysis, Moessbauer spectroscopy, chemical analysis, derivatographic analysis). A mechanism is proposed for the plasma-chemical regeneration of the samples. The reduction process is studied and the activity, the relative degree of transformation, the activation energies, the rate constants, the relative activity and the degree of thermal deactivation of the regenerated samples are determined. It is found that the samples are reduced three to five times as fast as the standard ones. The increased reduction rate and the high catalytic activity are due to the increased pre-exponent factor in the Arrhenius equation at constant activation energy. The causes for the high activity and thermal stability of the samples are explained. The advantages of the plasma-chemical technique are outlined as compared with the conventional methods for activation of spent catalysts for ammonia synthesis.