The differences of different band reflectance among water body, vegetation, urban area, soil and other objects are the foundation of extracting water body information by means of remote sensing data. Through analyzing the spectral characteristics of the water body information in remote sense images, the characteristics of MODIS image data and the methods for extracting water body information are introduced, and then the advantages and disadvantages of these methods and the effectiveness of the different water body indices are described in detail. The water body index is widely used to extract water body information. The results show that to apply different water body indices and spectral characteristics of MODIS data comprehensively can reduce substantially the influence of other different ground objects and extract water body information with a high precision, so to provide a quick and reliable basis for dynamic monitoring of water resources and water environment.