The comfort of maglev trains is related to the vibration in the passenger area of the vehicle and is determined by the acceleration and impact in three directions as the train passes over the track. The comfort of the maglev track is achieved by limiting the maximum acceleration and impact to not exceed specified limits. Unlike small-span maglev bridges, long-span bridges experience changes in deck alignment under the effects of temperature, wind load, and train load, which directly affect the vertical curve alignment of the bridge track. Based on the existing technical standards and related calculation principles and methods for vertical and horizontal curve minimum radii in current maglev track design, the relationships among the vertical acceleration, impact, and alignment and bending angles of the bridge track at the train operating velocity are determined. By verifying the instantaneous deformation curves of the bridge deck using the representative positions of the train's head, middle (center of the car length), and tail during travel, the technical index for the comfort of the bridge track during instantaneous bridge deformation are established. This paper provides the calculation loading method and results for the comfort of long-span bridges using a specific long-span maglev bridge as an example.