Anti-falling device for bridge side guardrail on upper portion of passing road surface and using method of anti-falling device

The invention discloses an anti-falling device for bridge side guardrails on the upper portion of a passing road surface and a using method thereof.The anti-falling device comprises two cantilever trolleys arranged side by side and an anti-falling support, wheels are arranged at the four corners of a base of each cantilever trolley, a supporting stand column is perpendicularly arranged in the middle of one end of each base, and a cantilever beam is perpendicularly arranged at the upper end of each supporting stand column outwards; the hanging stand columns are arranged at the two corners of the outer side of the horizontal frame body, the upper ends of the two hanging stand columns are in butt joint with the outer ends of the two cantilever beams respectively, and the position of the anti-falling support can be adjusted in the length direction of the bridge body by pushing the cantilever trolley. The anti-falling support can continuously move forwards to correspond to a construction area, dynamic protection o