Abstract: In the mixed area of ship lock and hub traffic bridge,there is collision risk between the ships passing through the lock and the traffic bridge project. Under the situation of the hidden danger of ship collision bridge control for three years,this paper adopts the finite element method to analyze the anti-collision performance of the traffic bridge of Changzhou three-line and four-line ship lock. The study shows that after 5 000 t ship crashing the sluice wall of the lock,the maximum displacement of the box girder is close to zero,and all the indexes of the traffic bridge meet the requirements of the code. This condition has little influence on the safety of lock and traffic structure. When 5 000 t and 3 000 t ship crash the bridge directly,the displacement of the box girder is large,which is easy to cause bridge damage.The development of large-scale ships increases the crashing risk in the mixed area of lock and traffic bridge. Compared with the condition of crashing the sluice wall of the lock,the ship crashing the box girder of the traffic bridge is more likely to cause damage to the bridge. Guidance and navigation aid signs should be improved to remind the ship to verify the compliance between the freeboard height of its own ship and the clear height of the bridge,so as to improve the safety of entering and leaving the lock.