Abstract: The number and variety of contaminants in rainwater harvesting cellars in rural areas of Northwest China make quality of cellar water inadequate to meet residents' safe drinking water standards．The use of a new energy-saving and efficient water purification process（gravity flow ultrafiltration technology）is an important means of improving quality of cellar water．On the basis of describing characteristics of water cellars in northwest region, factors such as membrane material, membrane components, inlet water quality, and membrane cleaning method that affect operational effects and mechanisms of membrane outflow, membrane fouling, or membrane blockage were analyzed．In depth exploration and analysis were conducted on technical and economic advantages of gravity flow ultrafiltration technology in application and promotion of rural areas in northwest China．It was proposed that gravity flow ultrafiltration technology was suitable for development of water scarce areas in rural areas of northwest China, in order to provide reference for improving quality of cellar water and ensuring safe drinking water for residents．