Due to the lack of facilities for the measurement and control of flow in U-shaped channels in some irrigation areas, a novel radial bottom plate gate is designed according to the section size of a U-shaped channel, which is composed of gate plate and gate piers. The hydraulic performance of this gate was studied by model test and numerical simulation with three shrinkage ratios of 1 ∶1, 2 ∶3 and 1 ∶2. The results of the model test show that the variations of water surface line of the gate with different shrinkage ratios are basically the same, but the head loss increases with the decrease of the shrinkage ratio. Therefore, the radial bottom plate gate with the shrinkage ratio of 1 ∶1 was selected as the measurement and control facility for U-shaped channels, and the flow measurement formula of gate hole was established. Then, Flow-3D was used to obtain the longitudinal flow velocity distribution and Froude number variation of the upstream and downstream sections of the radial bottom plate gate. The simulation results show that the flow velocity distribution in front of the gate with different opening degrees is consistent, and the maximum flow velocity is located at the perpendicular bisector and below the center of the free water surface. The Froude number of the upstream section is less than 0.5, which meets the current measurement conditions, and the maximum Froude number of the downstream section is concentrated in the free water surface close to the wall of the channel behind the gate. The research results can provide some technical support for the design and optimization of measurement and control facilities for U-shaped channels.