The invention discloses an anti-capsizing support of a bridge. The anti-capsizing support of the bridge comprises a first plate, a second plate and a third plate, wherein the first plate, the second plate and the third plate are arranged in parallel from top to bottom. Clamping grooves are formed in the two sides of a second insertion plate vertically. Each clamping groove communicates with a channel through a square hole between the clamping groove and the channel. A movable brake pad is placed in each clamping groove. A tie piece is arranged in the channel. Wedges are arranged on the two sides of the tie piece at intervals and face the same direction, and each wedge makes contact with the movable brake pad in the corresponding position. A threaded hole is formed in the end of the tie piece, and a tension bolt is installed in the threaded hole for tensioning connection. The anti-capsizing support of a bridge is of a pure mechanical structure, and long-term maintenance-free operation can be achieved; and in addition, main friction force happens to friction plates between the insertion plates, the automobile brake pads are used as the friction plates and are free of maintenance in the whole life, and the friction force of the brake pads can be adjusted conveniently through the tension bolt.