Using density functional theory, we studied the adsorption of an N(2)O molecule onto pristine and Si-doped AlN nanotubes in terms of energetic, geometric, and electronic properties. The N(2)O is weakly adsorbed onto the pristine tube, releasing energies in the range of -1.1 to -5.7 kcal mol(-1). The electronic properties of the pristine tube are not influenced by the adsorption process. The N(2)O molecule is predicted to strongly interact with the Si-doped tube in such a way that its oxygen atom diffuses into the tube wall, releasing an N(2) molecule. The energy of this reaction is calculated to be about -103.6 kcal mol(-1), and the electronic properties of the Si-doped tube are slightly altered.