Thermodynamic stability boundaries of nitrous oxide (N(2)O) hydrate and Raman spectra of the N(2)O and host water molecules in the N(2)O hydrate system were investigated in a temperature range of (275.20 to 298.19) K and a pressure range up to 305 MPa. Two three-phase coexisting curves of (hydrate + aqueous + gas) and (hydrate + aqueous + liquid N(2)O) originate from the quadruple point of (hydrate + aqueous + liquid N(2)O + gas) located at. (285.15 +/- 0.05) K and (4.2 +/- 0.1) MPa. The phase behavior of the N(2)O hydrate system is similar to that of the carbon dioxide (CO(2)) hydrate system up to 100 MPa, while the stability boundaries of the NO hydrate system are shifted parallel to the (2 to 3) K higher temperature side than that of CO, hydrate. Raman peak splitting of the intramolecular vibration mode for the nitrous oxide molecule in the hydrate phase indicates the occupancy of the nitrous oxide molecule in both small and large cages of structure-1, and this observation is also corroborated by the pressure-induced Raman shift of the lattice mode.