Abstract: Early warning system acts as an important role in improving the actively responding ability of human beings to control and mitigate geohazards. Especially, geohazards have occurred more and more frequently in recent years with the construction and resource exploitation in the Southwest of China. By the restriction of economic development and so on, however, only a part of geohazards have been controlled through engineering construction. Others need to be prevented with effective monitoring. This paper begins with some key points in order to establish early geohazards warning system. Then, it summarizes the main characteristics of modern information technology, and puts forward the data collection, remote wireless transmission, data organization and integration, and fast data mining method. They are base on Internet of Things, modern mobile communication and cloud computing technologies. Meanwhile, a real-time early geohazard warning system has been developed. The Longjingwan landslide is selected for example application. The results show that the methods are feasible. The system functionalities are reliability basically. They can provide a useful technology support for geohazards mitigating and preventing.