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Ganluo County is located in the southwestern part of Sichuan Province in China. It has strong geological tectonic movement, strong earthquake affected area and frequent debris flow disasters. There are two huge debris flows occurred in Zile Valley of Ganluo County in 1987 and 2019, a large amount of debris flow deposits went down the valley, destroyed the buildings at the mouth of the valley, causing huge property damage to local residents. In this regard, based on data of field survey and UAV aerial photography, the Arcgis and Massflow software were used to invert and analyze the movement characteristics of the debris flows occurred in 1987 and 2019, and the future activity characteristics of the valley are predicted. The results show that if the debris flow breaks out in the valley again based on the existing sources, the maximum mud depth will reach to 11.9m, the flow intensity will reach to 123.37m2/s, the total volume of material flushed out is 11.18×104m3 and the accumulation fan area is 6.925×104m2. However, after adopting reasonable engineering measures, the maximum mud depth is reduced to 8.5m, the flow intensity is reduced by 52.7% to 58.32m2/s, the accumulation fan area is reduced by 80% to 1.406×104m2 and the total volume of material flushed out is reduced by 75% to 2.75×104m3. This shows that the use of retaining measures to control the debris flow in Zile Valley can achieve good results.