A new type of variable friction damper is proposed and designed to improve the energy dissipation capacity and stability of the traditional friction damper. The new variable friction damper can achieve variable damping force output characteristics and have a certain anti-eccentric load capacity by adopting a reverse discontinuous slope structure design and a butterfly spring combination, and it can effectively improve the energy dissipation capacity of the damper, because the auxiliary friction plate is also added to the structure. Firstly, the mechanical characteristics of the damper in different working stages are analyzed by establishing a theoretical model, and the influence of various design parameters on the damping output characteristics of the damper is analyzed. Based on this, a prototype of the processing principle was designed and the mechanical characteristics were experimentally studied. Finally, the anti-eccentricity of the isolator was verified by the finite element method. The results show that the test results of the new variable friction damper are consistent with the theoretical analysis；the hysteresis curve is “dog-bone”，that is，the output characteristic of variable damping force can be achieved；compared with ordinary flat friction dampers，the frictional energy consumption can greatly improve the energy consumption capacity. Different damping characteristic outputs can be achieved to obtain different vibration isolation requirements by adjusting the value of the torque. The analysis results show that the new variable friction damper has a certain resistance to eccentric load.