Rubber tracks have recently been applied to the running gears of high-speed tracked vehicles, because they produce low traveling noise and cause less damage to the pavement compared with steel tracks. However, there have been few studies on the analysis of the vibration characteristics. In this study, free vibration of an axially moving rubber track is investigated both experimentally and analytically. The analytical model for free vibration and equations using the stiffness matrix have been developed to predict the fundamental effects of the tension and the track speed on the natural frequency. The results demonstrate that the proposed mathematical model could accurately assess the vibration characteristics of the axially moving track at high speeds.