Abstract: To explore the influence of sediment on the Basher trough under different channels and slopes. In this paper, the method of combining numerical simulation and experiment is adopted to lay natural river sand in the upstream of three channels under different slopes, stir them evenly in the water tank, keep their sediment content unchanged, and then set different inflow flows. The changes of sediment distribution, velocity distribution, flow measurement error and sediment carrying capacity in Basher trough under different schemes are analyzed. At the same time, the “fluent” software is used to carry out three-dimensional three-phase flow numerical simulation to verify the physical experiment. The results show that the water and sediment simulation by Euler model is consistent with the results, and the maximum error does not exceed 4.23%. In the Basher trough test, the maximum flow measurement error in all working conditions is 15.08% at the gradient of 0.8% in the U-shaped channel. The minimum flow measurement error is 2.13% at the gradient of 0.1% of the trapezoidal channel. Among the three channels, the flow measurement error under trapezoidal channel is the smallest, and the flow measurement error under U-shaped channel is the largest. The Basher trough of trapezoidal channel has the highest flow measurement accuracy, and the sediment distribution is concentrated on the upstream connection section of the Basher trough and both sides of the channel bottom. The trough has less sediment, which has little influence on the flow. The flow measurement accuracy can be satisfied well in the Basher trough with a slope of 0.1% to 0.4%, while the flow measurement error is larger in the Basher trough with a slope of 0.4% to 0.8%. At the same time, when the maximum measured water level is 34.44% to 53.33%, the flow measurement error of the Basher trough decreases rapidly. When the flow measurement error exceeds 53.33%, it decreases slowly, and finally the curve tends to be stable, and the flow measurement error is relatively small. When the water level of Basher trough is less than 15.49% of the maximum measured water level, the flow measurement error is relatively large. In the case of large flow, the sediment carrying force in most parts of the Basher trough is more than the average sediment content of the channel, indicating that there is no siltation phenomenon in the Basher trough in the case of large flow. In the case of large flow, the diffusion section has the maximum sediment carrying force, while in the case of small flow, the throat section has the maximum sediment carrying force.