To achieve the girder-end displacement control of long-span cable-stayed bridges under static and dynamic loads such as temperature, vehicle load, wind load, and earthquake, a new type of nonlinear spring and damping restraint device was developed in this paper, and a dynamic analysis finite element model of the structure was established. The influence laws of the limit parameter variations of the device on the girder-end displacement, the relative displacement between tower and girder, and the internal force at the tower bottom were analyzed, and reasonable parameter values were determined. On this basis, the dynamic responses of the long-span cable-stayed bridge before and after the installation of the device were compared and studied. The results show that the girder-end displacement decreases with the increase of the equivalent stiffness of the device and increases with the increase of the gap. The reasonable setting of the nonlinear spring and damping restraint device can greatly reduce the girder-end displacement of the long-span cable-stayed bridge under static and dynamic actions and will not cause adverse effects on the internal force distribution of the structure.