The occurrence of waterlogging disasters can seriously affect the safety of people's lives and property around rivers, and it is important to keep track of the water level changes in rivers in a timely and accurate manner. In response to the shortcomings of the current traditional water level measurement and monitoring methods in terms of timeliness and safety, a water level remote monitoring system based on a pulsed laser and a cloud platform is designed. The measurement device is based on an STM32 microcontroller, which emits a pulsed laser to a floating board in a measurement barrel, detects the distance from the device to the floating board on the water surface, and finally calculates the depth of the water level of the river to be monitored. Laboratory simulation results show that the relative error is less than 1.7% and the coefficient of variation is less than 1.2% when the water level depth is between 200mm and 800mm when the measuring device is fixed at a height of 1m. The wireless transmission module enables real-time uploading of water level data, and the cloud platform can accurately display the water level and measurement time, indicating that the remote water level monitoring system is feasible and can achieve real-time remote monitoring of river water level, and has certain application value.