The kinectic parameters were measured for the catalytic decomposition of nitrous oxide on ZnO powder between 40 and 60 kPa and the temperature range 725-835 K. Under studied conditions the reaction was found to be first order in N2O. An Arrhenius fit to the rate constants results in an apparent activation energy of 120 +/- 4 kJ mol(-1). Only the temperature-dependent nitrogen kinetic isotope effects were experimentally obtained, while the oxygen kinetic isotope effects were perturbed by O-18 exchanged between N2O and ZnO. Theoretical interpretation of KIEs was evaluated according to Bigeleisen's formalism. From comparison of calculated results with the experimental data both a cis ONNO and a fork-type NNOO models are acceptable as transition state of the reaction.