The angle resolved intensity and velocity distributions of desorbing product N(2) were measured under a steady-state N(2)O+CO reaction on Rh(110) by cross-correlation time-of-flight techniques. Three-dimensional intensity distribution of N(2) has been constructed from the angle resolved intensity distributions in the planes along different crystal azimuths. N(2) desorption has been found to split into two lobes sharply collimated along 50-63 degrees off normal toward [001] and [001] directions, suggesting that N(2)O is decomposed through the transition state of N(2)O adsorbed with the molecular axis parallel to the [001] direction. From the velocity distribution analysis, each desorption lobe is found to consist of two components with different peak angles, ca. 50 degrees and 74 degrees off normal. In both lobe cases, desorption components have been interpreted by the model of two adsorption sites; N(2)O at on-top site emits N(2) to 50 degrees and that at bridge site emits to 74 degrees.