Water quality is more and more important for people all over the world. But there are many problems in ordinary monitoring system for water quality such as untimely data processing, the lack and weakness of early warning mechanism for water quality change and so on. In this paper, one new remote water quality monitoring system was designed based on GPRS technology, after that the modules of the system were mentioned. Especially including the design and the working process of GPRS module, the design of the two main subsystem of the remote water quality monitoring system was described. The test of the remote water quality monitoring system based on GPRS proved that the system has the qualities of stable performance, reliability, well-maintain and low cost.