A triple-layer BP neural network was put forward based on the principle of the 8.5 μm, 11 μm, and 12 μm brightness temperature to retrieve the cloud phase in MODIS images. The cloud phase was retrieved based on the artificial neural network in high-latitude region(N30°～N55°) and low-latitude region(N0°～N30°) on January 15, 2008 and July 15, 2008 in China, and the result was compared with the cloud phase of MOD06 of NASA center. The result indicates that the inversion precision of the method is higher than 90%, and the uncertain scope of cloud phase is decreased.