The damping spacer is a flexible or semi-rigid spacer that can reduce the breeze vibration or sub-gap vibration of the split conductor. my country's 500kV transmission line adopts a four-split conductor structure. The spacer is the main fitting in the split wire structure. The basic tasks of the spacer are: to prevent the whipping between the wires, to suppress the vibration of the breeze and the vibration of the sub-gap. The most used is the damping spacer, which has better vibration absorption performance than the rigid spacer. Therefore, quantitative testing of the damping spacer's vibration-absorbing performance has become the key to research, design, manufacturing and selection of the damping spacer.