The invention provides a landslide disaster monitoring device, which comprises a vegetation remote sensing monitoring device, a seismic wave monitoring device, a groundwater monitoring device, a rainfall monitoring device, a determining device, a slope monitoring device, a data analysis device, a data transmitting device and an early warning device. The invention also provides a monitoring methodfor the landslide disaster monitoring device. The method comprises the steps of: acquiring the geological data of a landslide monitoring area, the geological data including vegetation image data, seismic wave data, groundwater data and rainfall data; determining whether a landslide may occur according to the geological data, if so, using the slope monitoring device to monitor the displacement of the slope that may cause the landslide, using the data analysis device to analyze the displacement of the slope to determine whether a landslide occurs, and if a landslide occurs, enabling the data analysis device to give an early warning signal; and receiving the early warning signal by the data transmitting device and converting the early warning signal into an intervention processing alarm and transmitting the intervention processing alarm to the early warning device. The landslide disaster monitoring device has high monitoring efficiency.