Abstract: Research purposes: Debris-flow is generally existed in the world of natural disasters, especially in central and Western China terrain complex area, debris flow every year caused great loss of life and property. Common gravity arresting dam control measures has the characteristics of big construction difficulty, high cost, large-scale governance project is difficult to spread, therefore, easy construction, low cost of new structure need to develop, in recent years, new flexible arresting net structure is considered to be gravity arresting structure effective alternative structures. Based on the model test of debris flow, set the two flexible arresting net and a gravity dam, by arresting structure at the rear part of the impact force and analysis is arresting provenance analysis, draws the following conclusions:(1) the flexible structure of arresting the arresting effects obvious, can effectively the solid substance intercept.(2) the porosity of arresting structure intercepted source particle size sorting, but porosity less than 0.8 of a median particle diameter has little effect, is greater than 0.8,the impact of increased dramatically.(3) flexible arresting structure can effectively relieve Mizoguchi position of impact pressure, the most upstream blocking structures subjected to impact is greater than downstream arresting structure.