Abstract: In order to study the dynamic response of the railway fabricated temporary emergency steel bridge under the action of train load, this paper establishes a vehicle-bridge coupled vibration system model, and studies its operation law, and analyzes the safety of trains under different train speeds. As well as the dynamic response of the bridge, the influence laws of the dynamic response of the temporary steel bridge when the train passes through the bridge at different speeds are compared. The results show that when the train passes the bridge at a speed of 60km/h, the dynamic response of the vehicle and the bridge meets the requirements of the specification; as the operating speed of the train increases, the dynamic response of the vehicle and the bridge also increases, but the influence curve is non-linear ; The recommended maximum speed of the train is 80km/h.