The utility model belongs to the technical field of viaducts, and particularly relates to an anti-cracking structure of an anti-collision wall of a viaduct, which is characterized in that a true jointand a false joint are arranged on the anti-collision wall at intervals, a maintenance device is arranged on the anti-collision wall, and a kerf is arranged on the false joint; the maintenance devicecomprises a water tank, a valve is arranged at a water outlet of the water tank, the water outlet of the water tank is connected with a plastic pipe, a plurality of water outlets are evenly formed inthe plastic pipe, the outer surface of the anti-collision wall is wrapped by felt, the plastic pipe is placed on the top face of the felt in the length direction of the anti-collision wall, and the plastic pipe and the outer surface of the felt are completely wrapped by plastic films. According to the cast-in-place anti-collision wall, the true joints and the false joints are reserved in advance,the false joints are cut, cracks caused by deformation of the box girder body are counteracted, and meanwhile drip infiltration maintenance is adopted, so that cracks on the surface of the cast-in-place anti-collision wall are reduced.