<p>To address the issues of wheel polygonal excitation intensifying metro vehicle system vibrations, worsening internal vibration transmission within components, and reducing vehicle operational safety, this study utilizes SIMPACK dynamic analysis software to establish a dynamic model of the metro vehicle system and investigate the impact of wheel polygonal wear on the dynamic response and vibration transmission characteristics of the metro vehicle. First, the vertical vibration characteristics of key components, such as the axle box, frame, and car body, are analyzed under different polygon orders and wave depths, as well as dynamic responses during straight and curved track operation conditions. Next, methods such as time-domain signal analysis, Hilbert-Huang transform (HHT), and short-time Fourier transform (STFT) are employed to explore the influence of polygonal wear on component vibration characteristics under various operational conditions. Finally, based on the frequency-domain responses under different operational conditions, vibration amplitude-frequency transmission characteristics are obtained and experimentally validated. The results indicate that the wave depth and order of wheel polygonal wear significantly affect the vehicle’s vertical vibration acceleration and operational safety. The suspension system can effectively mitigate vibration transmission, with the primary and secondary suspension systems exhibiting notable vibration isolation and damping effects for both high and low-frequency vibrations. This research provides technical support for optimizing metro vehicle suspension systems, reducing vibration and noise, and improving vehicle operation and maintenance.</p>