<p>Bridge train derailments are among the most common and severe consequences of ship collisions with bridges. This study simulates the dynamic response of bridges and trains under such collisions using finite element analysis, integrating practical engineering considerations. The paper analyzes and calculates the dynamic response of both the train and the bridge structure under ship collision by establishing a ship-train-bridge coupled model. Building upon previous numerical simulations of ship-pier collisions, this paper closely focuses on the Chongqi Railway-Highway Bridge, constructing a detailed simulation model that closely mirrors the actual structure. Simulations and verifications of sea-river ship’s impacts were performed and a system model for ship-vehicle-bridge dynamic coupling was established. Through finite element analysis, an in-depth examination of this coupled system was conducted. The numerical results indicate that ship collision significantly intensifies the dynamic response of the train-bridge system: the risk of train derailment rises sharply, with transverse vibrations far exceeding those in a no-impact scenario, challenging system stability. At the same time, the transverse displacement and acceleration in the mid-span region of the bridge show a significant increase, which further highlights the profound impact of the impact on the transverse dynamic response of the bridge structure. Additionally, the train's operating speed and its specific position on the bridge significantly impact the safe train operation, while the train's location on the bridge directly affects the lateral dynamic response of the bridge structure.</p>