Objective To analyze the microbial contamination of rural drinking water in She County from 2016 to 2020,and to assess the risk of transmission of infectious diseases by water. Methods According to the "Standard Test Methods for Drinking Water" GB/T 5750—2006,760 rural drinking water samples were collected from 28 towns in She County in 2016—2020 during the dry and abundant water periods.The total number of microbial indicators,coliforms and heat-resistant coliforms were detected on the collected samples.According to "Drinking Water Hygiene Standard" (GB 5749—2006),the microbiological indicators of the water samples were evaluated. Results A total of 760 rural drinking water samples were tested,with a qualified rate of 73.03% (555/760),with an increasing trend in the annual qualified rate χ²_trend=57.644,P<0.001).The qualified rate of water samples in the abundant water period was higher than that in the dry water period,and the difference was statistically significant (χ²=26.512,P<0.001).There was no statistically difference between the qualified rate of the factory water and the peripheral water samples (χ²=0.167,P=0.744).Among the three microbial indicators,the qualified rate of heat-resistant coliform was the highest (81.32%),and of total coliform was the lowest (73.82%),the difference between the three was statistically significant (χ²=14.831,P<0.001).The qualified rate of completely treated water samples was higher than that of incompletely treated water samples,with a significant difference(χ²=42.533,P<0.001). Conclusion In the past 5 years,She County rural drinking water microbiological indicators qualified rate report shows that there is a risk of infectious disease transmission by water.It is necessary to strengthen the management and monitoring of rural drinking water to protect the health of residents.