This paper describes the formation and the development of debris flows in the mountains of south Shaanxi Province, The evolution through time and space and lesser the regulirity of the regional distribution are mainly discussed in七his paper,According to the forms of gullies and the development of debris flows,the debris flows can be classified into four types:(1)typical gully debris flow;(2)gully debris flow;(3)slope debris flow;(4)slope surface debris flow. Several proposals concerning the control of debris flows in a comprehensive way for a long time are put forward on the basis of the developing tendency of debris flows,A distribution map of the debris flows in the mountains of south Shaanxi Province is given in the paper. Thus,the paper provides scientific basis for the economical development of the mountain region.