In the paper,a landslide monitoring system based on GNSS technology and multi-sensor fusion is developed.RT-Thread operating system realizes multi-task processing and low-power mode operation,has the functions such as communication with landslide monitoring and early warning cloud platform,GNSS network RTK real-time dynamic high-precision positioning,multi-sensor fusion,real-time monitoring data acquisition and processing,and early warning of landslide geological disasters.The experiment results show that the system has low operating power consumption,fast data transmission speed,high reliability,and displacement monitoring accuracy can reach the millimeter level,which meets the needs of high-precision deformation monitoring and early warning of landslide bodies.