The attenuation, delay and susceptibility to interference of suspension sensor was analyzed in the process of signal transmission for middle-low speed maglev train, and the solutions were proposed. Firstly, the equivalent model of signal transmission system was established, the working parameters of main devices were optimized according to the principle of impedance matching, from which the attenuation distortion of signal transmission through long cable can be prevented. Secondly, the maximum delay of sensor signal required by the dynamic response of suspension system was analyzed, comparison experiment based on vibration table was also designed and implemented. Finally, according to the characteristics of electromagnetic environment for the signal transmission, the filter circuit and the measures including shielding and grounding were designed, tests such as radio frequency radiation induced by immunity and pulse group immunity were passed. The results show that the dynamic characteristics of suspension system are not affected by the delay of signal serial communication, and the proposed solutions can realize accurate, timely and reliable signal transmission.