Karst water is an important part of the Beijing groundwater. The division of karst water is helpful for choosing evaluation methods,exploitation ways and protection measures of different karst water systems.The survey was based on the remote sensing images of SPOT5 in 201.On the basis of image pre -processing and the existing working foundation, and in combination with the field examination and arificialinterpretation, this research obtained the spatial distribution characteristics of geological formations, topography and geomorphology, drainagesystem.Bby analyzing the relation between each factor and the development of karst, we divided into two level of karst water system in west Beijing,including four level l and five level Ⅱ . Compared with the previous classification results, we hope to provide technical support for karst waterdevelopment and utilization in west Beijing.