Research conclusions ： This new method not only contains the free stationing feature of leveling but also eliminates the error by virtue of the height measuring of the equipment and the prism during surveying with high feasibility and efficiency. It is proved this is a good way to solve the problem between railway girder precision adjustment in vertical control network above the bridge and ground vertical control network during construction. Comparative analysis is made in this paper to prove the new method is much more superior than that of traditional trigonometric leveling. The precision can satisfy second - order leveling under observation conditions of suitable distance( ≤60 m) and suitable vertical angle (≤20°) if a suitable Total Station is used.