In order to strengthen beam-column joints, avoid the failure mode of "weak joints" in frames and improve the overall seismic and energy consumption capacity of frame structures, a displacement-amplified torsion damper (DATD) with independent intellectual property rights is developed. Numerical analysis and experimental study of DATD were carried out. Firstly, a total of 18 models of DATD with different parameters were designed and their finite element models were established, and then numerical analyses were performed. Then a DATD was designed and manufactured. The results of finite element analysis were verified by performance tests. The results show that the DATD has full hysteretic curve and strong energy dissipation capacity. The hysteretic curves of finite element analysis and performance test are in good agreement, and with the increase of loading displacement, the difference between them decreases. So, the finite element model established in this paper can be used to study the mechanical properties of DATD. Finally, the parameter influence analysis of DATD was performed, the influences of the diameter of the lead core, the distance between the lead core and the central axis, the diameter of the rubber layer, the thickness of the rubber layer and the rubber shear modulus on its characteristic parameters were studied. The results show that the yield shear force, equivalent stiffness, equivalent damping ratio and the energy dissipation coefficient of DATD increase obviously with the increase of the diameter of the lead core, and increase slightly with the increase of the distance between the lead core and the central axis. With the increase of the diameter of the rubber layer and rubber shear modulus, the yield shear force and equivalent stiffness gradually increase, while the energy dissipation coefficient and equivalent damping ratio gradually decrease. The four characteristic parameters all decrease slightly with the increase of the thickness of the rubber layer.