Steel spring vibration isolators, as key components under the floating slabs of rail transit, can seriously affect the safety of train operation performance when damaged. Due to their concealed nature, damage is difficult to detect through conventional inspection. Conventional static sensor deployment methods are not suitable for long-distance inspection. This study has developed a dynamic inspection and monitoring system and analyzed the impact of isolator damage on vehicle body vibration. Firstly, a dynamic monitoring system for rail transit was established, and dynamic response data of the metro vehicle body during operation were collected. Then, a vehicle-track coupling dynamic model was established using ABAQUS and SIMPACK software, and the correctness of the model was verified by comparing with the measured data. To more accurately simulate the irregularities of metro tracks, a full-band track excitation spectrum was constructed by combining the American six-level spectrum and the Sato short-wave spectrum, covering both medium and long waves and short waves, thereby improving the model accuracy. The model was used to determine the damage factors affecting the vehicle body vibration response, and finally, a quantitative analysis of the influence of multiple damage factors on the vehicle body vibration response was conducted. The results show that the dynamic monitoring system can be used for long-distance inspection of isolator damage in rail transit. For the smoothness index, the degree of damage has the most significant impact, with a weight of 52.2%; the location of damage is the second most influential, with a weight of 25.4%, and the impact is most significant when located at the junction of the floating slabs; the number of damages has a relatively limited influence, with a weight of 22.4%. For the acceleration extreme value, the weight of the degree of damage is 46.6%, the weight of the location of damage is 33.9%, and the weight of the number of damages is 19.5%. The research results can provide a basis for the identification and application of rail transit steel spring isolator damage inspection systems..