The utility model discloses a dilatory synchronous traction system of bridge, its characterized in that traction system include the two sets of symmetry set up in the hoist engine mechanism of bridge both sides, hoist engine mechanism includes hoist engine, standing block, running block and in proper order around locating the wire rope on the three, the hoist engine is fixed in the bridge outside, the standing block is fixed in on the fixed basis in bridge the place ahead, the running block is fixed in bridge side marginal part, it lies in the two sets of to be provided with on the fixed basis guide pulley between the standing block, the two sets of wire rope warp in the hoist engine mechanism guide pulley turns to the back series connection and is one. The utility model has the advantages that, through making two hoist engine mechanism share a wire rope, realize pulling in step the bridge, simultaneously through increasing the detour number of turns of wire rope between standing block and running block to increase the traction force of standing block to the running block.