An approach is developed for inferring cloud top height (CTH) by using two shortwave infrared (SWIR) channels (i.e., 1.24- and 1.38µm) with similar cloud scattering and absorption properties but very different water vapor absorption properties. This channel combination is used to accurately infer the column water vapor amount above the clouds, from which the CTH can be retrieved. The approach performs best for ice clouds located in the upper troposphere. For those clouds, our approach performs as well or better than the current operational cloud height retrieval algorithm adopted by the MODIS science team. Citation: Wang, C., S. Ding, P. Yang, B. Baum, and A. E. Dessler (2012), A new approach to retrieving cirrus cloud height with a combination of MODIS 1.24- and 1.38µm channels, Geophys. Res. Lett., 39, L24806, doi:10.1029/2012GL053854.