To investigate metal limit damping device suitable for long-span railway bridges, formulas for calculating the mechanical properties of a metal limit damping device were established, and a simplified design method for the device was proposed. Meanwhile, the device design analysis software was developed with the combination of related design codes and the simplified design method. By taking a typical half-through arch bridge in Zhengzhou-Wanzhou high speed railway in China as the research object, the design parameters of the bridge limit damping device and three connection structural schemes were proposed. The proposed formulas were used to calculate the mechanical properties of the device, the solid finite element model of the device was established, and the influence on the seismic performance of the bridge was analyzed. Results show that the proposed design method of metal limit damping device had strong adaptability and high calculation precision, which met the accuracy requirement of engineering applications. The device could fulfill the driving comfort and safety demands of high speed railway bridges with good effects of seismicity mitigation and energy dissipation, and it reduced the displacement of the beam end for the long-span bridge by about 20%.