Water bodies are fundamental components of ecosystems, with the quality and quantity of water sources directly impacting the survival and reproduction of plants and animals, thereby upholding the ecological functions of wetlands, forests, and rivers. Traditional water quality monitoring methods typically involve manual sampling and laboratory analysis, which is time-consuming, labour-intensive, and lacks the capability for online monitoring. The monitoring system based on STM32 fails to deliver remote real-time monitoring and observation. While WiFi communication technology enables remote communication, it has limitations in transmission distance. This paper introduces a water quality monitoring system designed using NB-IoT technology. The STM32F103 microcontroller serves as the primary control chip, and in conjunction with sensors and NB-IoT technology, automatically uploads water quality data, including pH value, TDS value, and temperature value, collected by the sensors to the Internet of Things cloud platform, enabling online remote monitoring of water quality.