Abstract: To Kala region in middle reaches of Yalong River, according to the forming conditions of debris flow, five indexes including slope, lithology, density of collapsing and sliding point, buffer zone of geological structures and NDVI were selected to evaluate the hazard degree of debris flow based on GIS. AHP combined with information value method is used to determine the weight of the five indexes and hence divide the region into zones of different hazard degree. The results show: the area of debris flow valley in extremely low dangerous zone only accounts for 3.71% of all dangerous zones while in moderately dangerous zone and above, the area of debris flow valley accounts for 75.24% of the total area of debris flow valley in the whole region, corresponding well with the practical development condition, which proves that the quantitative analysis by the spatial analysis function of GIS combined with AHP and information value method is reliable in hazard zoning of debris flow.