The application of damping-rings to rotor/stator components in aero-engine was proved effective in protecting labyrinth air seals and the cylindrical walls of annular chambers against flexural vibration and fatigue failures excited by various disturbing forces. In view of the possibility of resonance, determination of the vibration characteristics of the labyrinth air seals with damping-rings by theoretic model, experiment or both is of vital importance in the design and development procedure. This paper built up the equivalent linear model of interface between the seals and damping-rings by introducing the local contact stiffness, and then researched the forced response of labyrinth air seals with two types of damping-ring under single-point exciter with sine signal. The dynamic response experiments of the shell with different damping-rings verified the validity of the proposed simplified model and the simulation results. The influence of variable parameters, such as the width and installed position of damping-rings was also discussed. In the experiments the damping-ring showed the great effect in vibration control by friction damping and contact stiffness.