Abstract: The faults caused by the pipeline vibrations are summarized in this paper. For studying the leakage of the pipeline in the engine's working process, in the running system, the dynamic characteristics are analyzed by the modal test. The results indicate that the natural frequency of some pipelines is in the range of the pump working frequency, and some frequencies are low. In view of this situation, the design of the pipelines is optimized. The comparison of the dynamic characteristic analysis results after the optimization shows that the natural frequency of some pipelines is increased and goes above the pump working frequency, and the dynamic environment of the lines is improved.