Based on the double distribution function shallow water Lattice Boltzmann Method，a transport model of supersaturated total dissolved gas (TDG) is established to study the influence of downstream channel regulation structures of a power station on the transport law of TDG in the river channel.The results show that the construction of regulation structures has little influence on the changes of flow pattern and TDG in the mainstream area.The influence of waterway regulation structures on the temporal and spatial distribution of supersaturated TDG is mainly characterized in the local area near the regulation structures.The flow velocity in the back-flow area of the dam field is reduced，and the mass transfer of the water body is weakened，resulting in the decrease of TDG concentration and the increase of the area of the low concentration area，which can provide a certain refuge space for fish.This study provides a new method for the study of TDG transport and diffusion in water bodies，and provides a scientific basis for improving the adverse effects of TDG supersaturation on fish caused by power station discharge and building ecological waterways.