According to the hydraulic calculation principles of the orifice outflow, the discharge capacity of the columnar reversing gate under the partial opening condition was calculated and checked. Using ANSYS, a large finite element analysis software, the discharge process was simulated. The distribution rule of the velocities in the gate chamber and downstream channel was obtained. An FEM model of the columnar reversing gate was built, and the natural vibration properties of the gate were analyzed. Based on the Westergaard added mass method, the added mass caused by the fluid-structure coupling motion was taken into account, and the effects of the coupling interaction were discussed. The results show that the size of the small gates meets the demand for discharge capacity, the current in the gate chamber is quite turbulent, the trunnion and arms are obviously impacted by flow, and the effects of water on vibration characteristics are remarkable. The study provides a reference for the design and calculation of gates of the same type. According to the hydraulic calculation principles of the orifice outflow, the discharge capacity of the columnar reversing gate was the partial opening condition was calculated and checked. Using ANSYS, a large finite element analysis software, the discharge process was simulated. The distribution rule of the based on the Westergaard added mass method, the added mass caused by the fluid-structure The results show that the size of the small gates meets the demand for discharge capacity, the current in the gate chamber is quite turbulent, the trunnion and arms are obviously. impacted by flow, and the effects of water on vibration characteristics are remarkable. The study provides a reference for the desig n and calculation of gates of the same type.