The invention discloses an anti-falling chain mechanism. The anti-falling chain mechanism comprises a gear and a chain, the gear is meshed with the chain, the chain is formed by hinging a plurality of chain links, each chain link comprises two connecting plates and two chain columns, the two chain columns are arranged in parallel, the two connecting plates are located on the two sides of the chain columns, swing arms are arranged at the two end parts of the chain columns, the swing arm of the chain column is rotatably connected onto the connecting plate through a torsional spring, two torsion beams of the torsional spring are respectively fixedly connected onto the connecting plate and the swing arm, a tooth of the gear comprises a front section and a rear section, the front section inclines towards the direction opposite to the rotation of the gear relatively to the rear section, the swing arm is at a horizontal state before the chain column and the teeth of the gear are in contact, and the swing arm rotates clockwise after the chain column and the teeth of the gear are meshed. When the swing arm rotates, the swing arm produces a moment of force opposite to the rotation direction under the action of the torsional springs at the two ends, so that the chain column is pressed on the teeth of the gear, the chain column is relatively firmly pressed on the teeth of the gear, and does not fall of easily.