The invention discloses a damper slippage prevention device for an overhead transmission line. The damper slippage prevention device comprises two hinged tong arms; a nut clamping hole is formed in one of the two tong arms; a bolt clamping hole is formed in the other tong arm; handle parts of the two tong arms are connected through an elastic mechanism; the elastic mechanism comprises a bolt and a spring, wherein the bolt penetrates through handles, and the spring sleeves the bolt and is located between the handles. An installation method for a traditional damper is not changed, therefore the holding force of the damper is increased; the axial movement of the damper is prevented; the problems of slippage and drop of the damper are solved once; the phenomenon that the damper slips, recovers, slips again and recovers again in a zone that the slippage and the drop of the damper frequently occur is avoided; the abrasion of a ground lead is effectively avoided.