The novel shape memory alloy-triple friction pendulum bearing (STFPB) is an advanced seismic isolation device that incorporates shape memory alloy (SMA) cables into conventional triple friction pendulum bearings (TFPBs). This study elucidates the design principle and structural configuration of STFPB and analyzes the factors influencing its performance. Results indicate that for optimal STFPB design, the effects of cable diameter on stiffness and energy dissipation capacity must be considered. Appropriately increasing SMA cable quantity effectively enhances stiffness and energy dissipation. A three-span continuous girder bridge model is simulated using the finite element software ABAQUS for seismic time-history analysis, and the fragility curves for piers and bearings are derived through fragility assessment. Findings reveal that STFPB exhibits superior seismic isolation performance to TFPB. Under strong earthquakes, STFPB effectively protects the main girder from excessive damage by leveraging its robust self-centering capability and high energy dissipation capacity.