Abstract: Water resource scarcity is a big problem in North China, especially in the northern part of the loess plateau. In the hilly areas, rainwater is the sole water resources and its harvesting is the only way to abatedrought. The common problems are that some rainwater storing reserviors have little water to store while the others are often overflowed. These are led by unclearing the rain water potential of the area. And the reservoirs built are failedto restore the proper amount of collecting water. Inthis paper, two new indices relative to rainwater harvesting are suggested. Oneis collectable rainwater resource potential of a region and another is runoff harvesting capability of a localarea. Based on GIS, RS and GPS techniques, the terrain and land surface of the study area are depicted. Thecollectable rainwater resource potentials of the region under 3 kinds of hydrological frequency year(drier,normal and wetter) are then calculated. And the runoff harvesting capability oflocal areas are computedwith models complied with Visual Basic programming language. The results can beused for designing the rainwater harvesting projects of the region.