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A remote real-time multi-parameter water quality monitoring system is proposed based on ZigBee wireless sensor network and GPRS technology. The CC2430 communication module is the core of the wireless sensor network. The data collected by the sensor nodes are sent to the coordinator node by the routing nodes, which are transmitted to the monitoring center by GPRS module in-timely. The signal conditioning circuits are designed, by which the weak electrical signals from the sensor electrodes are amplified and filtered. The time synchronization mechanism is utilized to wake up the nodes in the network in the same time, which significantly improves the stability of the network. The system has been continuously tested for several days. The average network packet loss rate is less than 1% within the communication distance of 100-meter. The average relative deviation of the pH value and dissolved oxygen concentration are less than 1%. The test results illustrate that the system has the advantages of flexibility, good real-time performance, high accuracy, stableness and reliability, and has a strong practical value.