With the continuous progress of rural construction, the problem of rural drinking water pollution is increasingly prominent. In view of water pollution, a design of rural drinking water monitoring system based on wireless sensor networks is proposed that nodes take STM32 as the core chip and WLK01L39 as well as its peripheral circuits are used as wireless communication modules and Beidou S1216 is used as GPS module to realize node localization. At the same time, the corresponding communication protocol and time synchronization algorithm are proposed. This paper have achieved automatic collection of water quality indicators, and uses GPRS network to achieve data upload. Experiments show the power consumption and data transmission performance of the system, and the packet loss rate is 6.2% when the communication distance of the system data is 150m in open area.