The invention provides a river estuary water quality monitoring device based on a PIC chip. The monitoring device comprises a buoy, a bottom barrel, a micro generator, a micro water turbine, a computer control panel, a vertical support, an indicator lamp, a lampshade, a transmitting antenna, a connecting pipe, a tee joint, a first water pump, a second water pump, a tail vane, a sensor set, a storage battery, a first connecting rod, a second connecting rod, a universal joint, a rocking hammer and a micro control chip. A light indicating mechanism is composed of the vertical support, the lampshade and the indicator lamp; the sensor set, the computer control panel and the transmitting antenna form a riverway water quality monitoring mechanism, and the first water pump, the second water pump,the universal joint, the first connecting rod, the second connecting rod, the rocking hammer, the micro water turbine and the micro generator form a wave energy power generation mechanism. The energyof the monitoring device comes from riverway wave energy, the monitoring device is environmentally friendly and does not pollute rivers or coastal waters, and the water quality can be monitored in real time without manually replacing a battery of the monitoring device.