Carbon dioxide pressure-broadened ro-vibrational transitions belonging to thev^2＋3v^3 band of H2160 have been measured with a sensitive cavity ring-down spectrometer. Water vapor of relatively low pressures （〈0.5 Torr） was used to limit the self-collisions among water molecules. After the calibration using the precise atomic transitions of Rb and a thermo- stabilized Fabry-Perot interferometer, 10^-5 cm^-1 frequency accuracy has been achieved. Line parameters are derived from least-squares fitting of the spectra using the ＂soft＂ collision model. The retrieved line parameters can be applied in the study of water absorption in the CO2-rich atmospheres of planets like Venus and Mars.
