In view of the difficulty of water quality monitoring and regulation in aquaculture industry, a water quality monitoring unmanned vehicle system is designed and developed by using NB-IOT technology, which can realize autonomous cruise collection of water quality and real-time monitoring and regulation of water quality in the cloud platform. The integrated navigation of digital compass, BD-GPS and IMU is used to realize the autonomous cruise and motion data acquisition of the unmanned vehicle. During the navigation, the water quality data is collected by pH, turbidity and dissolved oxygen sensors, and then the water quality and motion data are uploaded to the OneNET cloud platform through NB-IOT module. Taking dissolved oxygen regulation as an example, the water quality regulation node is designed to receive the cloud platform instructions to control the aerator, so as to achieve dissolved oxygen regulation. The experimental results show that the system can achieve the design goals and requirements well. In the cloud platform, the system can observe the water quality and movement information in real time, and issue instructions to control the aerator to adjust the dissolved oxygen content. After 25 minutes of remote opening, the dissolved oxygen content increases by 0.11mg/L. The system inspects 9 target points of a pond with an area of about 1 hectare, the average time is within 5 minutes, and shows good performance.