Abstract: The authors in this paper,according to the system analysis of stratum,constitution and landform,through studying the formation,the development and the characteristics of landslide,put forward the conception of pre-estimating landslide firstly based on the geologic structure cybernetics.The pre-estimating system for landslide is a technical method,which can determine the space position and the type of landslide,and can pre-estimating its developmental condition in the future without any exploration means,but according to all kinds of geological pre-estimating methods and topographical features of landslide.The authors build the basic system,the discriminating method and the working procedure of this technical method.They have applied this method to investigating the geological disasters along highways in Southern Shaanxi.This method has noboth theoretical and practical meaning.