A highly active catalyst for the decomposition of N2O was prepared by the thermal treatment of CoLaAl-hydrotalcite. For this catalyst the reaction rate was determined at various partial pressures of N2O, O-2 and H2O in a temperature range from 573 K to 823 K. The kinetic simulation resulted in a mechanistic model. The energies of activation and rate coefficients are estimated for the main steps of the reaction.