Abstract: Debris flow is a kind of disaster,which happens frequently and has serious harm to the nature. Longnan,as one of the very severe areas,hit by debris flows,landslides not only seriously impede the normal operation of G212,but also affected the regions economic development and peoples lives. Through dealing with the investigation statistics of the 232 debris flow gullies along G212 Longnan section in different attributes,different stages of development,as well as the different degree of harm,and combining the fractal theory,we have analyzed the quantitative relationship between the debris flow number and the landscape elements. The results indicate that topographic factors have different influences on debris flow with different attribute,different stages of development and different degree of damages; to some extent,integrated fractal dimension,shape parameters and terrain slope parameters in forming regions all can reflect the quantification features of different types of debris flow.