Due to the flexibility of long-span bridges, long-span bridges are widely used in railways. But the ballast track is frequently adopted in the track system of long-span bridges on China Passenger Dedicated Lines (high-speed railway). In order to improve the stiffness and geometric smoothness of track and unify the track form in the same section of the passenger dedicated lines, the laying of the ballastless track on long-span bridges has become a research hotspot. This paper taking the (35 + 40 + 60 + 300 + 60 + 40 + 30) m cable-stayed bridge on Nanchang-Ganzhou passenger dedicated line as an example, for bridge stiffness, Continuous Welded Rail on bridge, line during operation phase and durability of track structures, the adaptability of the ballastless track system on the bridge is fully studied. In this case, it is seen that ballastless track laying on a long-span bridge is a practical and feasible method, which can effectively reduce track maintenance, increase track safety and smoothness, as well as shorten the time it takes for passengers to travel.