In response to the problems in Chinese major monitoring system of water quality such as weak sampling capability of water quality

untimely data processing and lack of early warning mechanism of water quality change

based on GPRS technology

the design scheme of an automatic water quality monitoring system is proposed.The system composition is described

and the working process of GPRS module

together with the key part of the sub-system of monitoring center is introduced.The software design of the sub-system of water quality collection is explained

the multi-state

multi-task

multithreading software designing idea is advanced.The GPRS module flow is analyzed and the systematic function is achieved.Tests show that the system has stable performance

good timeliness and low operation cost

which can meet the need of water quality monitoring under the new situation.