In recent years，China’s economy has grown rapidly，and people’s living standards have greatly improved. With the ensuing requirements for drinking water quality have become more stringent. Due to micro-pollution，brackish water，fluorine，arsenic heavy metals and other water sources Problems，water plant processes，and secondary pollution of the water distribution network caused some indicators of drinking water in some areas to fail to meet the requirements of the “Sanitary Standard for Drinking Water” （GB5749-2006）. This article analyzes the current status and existing problems of drinking water in China，and the demand for high-quality drinking water in rural areas and campuses. By studying the nanofiltration process，it is found that nanofiltration can effectively remove suspended matter，colloids，calcium and magnesium ions，sulfates，bacteria，Virus，while retaining potassium and sodium ions and other beneficial elements to the human body，improve and enhance water quality，the effluent is better than the national standard，and it can be directly consumed. Carry out applications and obtain a good demonstration effect to provide reference for guaranteeing the provision of high-quality water supply in the Guangdong-Hong Kong-Macao Greater Bay Area.