A viscoelastic damper is a vibration-damping device that effectively absorbs energy against vibrations of various amplitudes. Viscoelastic materials convert absorbed energy into heat, which increases internal temperature and reduces performance. It is necessary to consider the performance degradation of viscoelastic materials to reduce the response of high-rise buildings due to long-period earthquakes. This paper presents a seismic response prediction method for high-rise buildings that considers the performance degradation of stud-type nonlinear viscoelastic dampers.