The utility model discloses a bridge dynamic loading monitoring system. The system includes: set up and know detection device and car weighing device, set up vehicle traveling track detection device in the bridge that awaits measuring, set up the information processing apparatus who knows detection device and bridge dynamic loading monitoring system in the vapour car logo who waits to monitor the lower bridge end of bridge in the vapour car logo of the last bridge end of waiting to monitor the bridge. The system knows detection device and car weighing device and acquires the weight information that is got into the bridge and leave diagnostic information and the vehicle of the vehicle of bridge through setting up on the bridge bridge end and the vapour car logo of bridge end down, and the while is acquireed and is obtained the dynamic positional information of vehicle when passing through the bridge through setting up vehicle traveling track detection device in the bridge, and the information monitoring when above -mentioned vehicle passes through the bridge is all by the information processing apparatus of the system of conveying. The application range of this system is extensive, and the real -time is good, and it is high to detect the precision, and has advantages such as simple to operate, low cost.