The ladder track is a new type of elastically supported vibration-reduction track system that has been applied to several urban railways in China. A field experiment was carried out at the trial section of an elevated bridge on Beijing Metro Line 5 where the ladder track is installed. The vibration responses of rails, sleepers, bridge deck, and the surrounding ground surface were measured when the train traversed on the ladder track and on the common non-ballasted slab track. The data were analysed in the time domain and the frequency domain. The experimental results show that as compared to the common non-ballasted track, the ladder track has special vibration reduction characteristics.