Track irregularity is the primary source of excitation that induces the dynamic response of trains, and when the irregularity exceeds a certain threshold, it significantly reduces the operational stability of the high-speed maglev vehicle-guideway system. This paper, based on the coupled vibration model of high-speed maglev trains and guideway, calculates the dynamic response of high-speed maglev trains and beams under irregularity excitation within different wavelength ranges. It investigates the impact of the wavelength of track irregularity on the dynamic response of the high-speed maglev train-guideway coupled system and summarizes the sensitive wavelength ranges of track irregularity for high-speed maglev. The results show that the dynamic performance indicators of the train and guideway are positively correlated with the amplitude of track irregularity, which is more pronounced at sensitive wavelengths. Among these, short-wavelength irregularity has a significant impact on the air gap, while long-wavelength irregularity is the main factor affecting the smooth operation of the vehicle. The research findings provide a theoretical basis for optimizing the operational stability of high-speed maglev trains and are of guiding significance for actual operation and maintenance.