The utility model discloses an anti-falling device, which comprises anti-falling outer frames and movable plates, wherein the adjacent anti-falling outer frames are sequentially connected end to end, and are arranged in the extending direction of a transmission line iron tower or concrete pole; one end of each moving plate is connected with the transmission line iron tower or concrete pole in a rotating way, and the other end of each moving plate is erected on the corresponding anti-falling outer frame; the ends, close to the anti-falling outer frames, of the moving plates are higher than the ends, away from the anti-falling outer frames, of the moving plates. According to the anti-falling device adopting the technical scheme, suspension loops of safety belts are arranged on the anti-falling outer frames in a sleeving manner, pass through the moving plates, and can move without the influence from the moving plates; if operating personnel accidentally fall, the suspension loops can be prevented from further falling by the moving plates closest to the suspension hoops, and the operating personnel are further prevented from further falling; the adjacent anti-falling outer frames are sequentially connected end to end, so that safety protection gaps in the adjacent anti-falling outer frames in a climbing process are avoided, and a real-time full-course protection function can be realized during the climbing of the operating personnel.