The angular and velocity distributions of desorbing products were analyzed in the course of a catalyzed N2O + CO reaction oil Pd(110). The reaction proceeded steadily above 450 K, and the N-2 desorption merely collimated sharply along 45degrees off the surface normal toward the [001] direction. It is proposed that this peculiar N-2 desorption is induced by the decomposition of adsorbed N2O oriented along the [001] direction. On the basis of the observation of similar inclined N-2 desorption in both NO + CO and N2O + CO reactions, the N-2 formation via the intermediate N2O(a) dissociation was confirmed in catalytic NO reduction.