Abstract: Taking the Dahonghe (DHH) section of the Hongruhe river as an example, based on Google Earth and ArcGIS 10.2 platform, the evolution of DHH before and after artificial cutoffs is analyzed. The results show that the DHH river lengths before and after the cutoffs are 166 and 74.5 km, respectively; the channel sinuosity is 2.95 and 1.32, respectively; the gradient of the river is 0.018‰ and 0.025‰, respectively. The length of the DHH decreases sharply and the gradient of the river increases due to the cutoffs. The river changes from a meandering to a straight channel. After the cutoffs, the flood discharge capacity of the DHH is improved, but it also leads to the increase of the flood peak of the river, which may aggravate the regional flood disaster to a certain extent.