In view of the dynamic characteristics of planar vertical-lift gates with large aspect ratio under the influence of pulsating pressure from water flow, the natural vibration frequency of the middle hole gate of the Jinhui Harbour South Gate was obtained through the analysis of natural vibration characteristics.The pulsating pressure on the gate model under different conditions was measured through physical model tests. The power spectrum functions of pulsating pressure at various measurement points were obtained through spectral analysis using the fast Fourier transform technique. These results were compared with the natural vibration characteristics to determine whether resonance would occur. The measured pulsating pressure was converted into nodal loads for finite element calculations, and random vibration methods were employed for numerical simulations to analyze the flow-induced vibration response of the gate, yielding results for dynamic displacement, dynamic stress, and other response factors under different gate opening conditions. The research results show that the dominant frequency of the pulsating pressure is below 1 Hz, with a large offset from the first-order natural frequency of the gate, which is 1.42 Hz, making resonance unlikely. The dynamic displacement response of the gate is less than 0.25 mm, and the maximum total stress is 8.15 MPa. Under various gate opening conditions, the dynamic response of the gate remains within the allowable structural range, indicating a high level of safety.