The invention discloses an anti-falling safety device of a lifting scaffold, and particularly relates to the technical field of scaffold falling prevention. The anti-falling safety device comprises a supporting plate, a storage groove is formed in one side of the supporting plate, a storage mechanism is arranged in the storage groove, and a mounting mechanism is arranged on the other side of the supporting plate; the storage mechanism comprises a transmission lead screw, the transmission lead screw is sleeved with a first threaded ring, and a second threaded ring is arranged on one side of the first threaded ring. The storage mechanism is arranged, a servo motor rotates forwards to drive the transmission lead screw to enable the first threaded ring to move leftwards, meanwhile, the second threaded ring moves rightwards under the action of threads, in this way, a stretching elastic strip begins to contract, therefore, rapid closing and storage of a protective net are achieved; multiple buffering protection effects are achieved in the protective net, the buffering effect is effectively achieved, safety is greatly improved, operation is easy, use is easy, more time and labor are saved, the repeated utilization rate is higher, and practicability is better.