Abstract: In order to effectively analyze the dynamic changes of risks during the operation period of urban bridges and predict their development trends, a research on risk situation assessment of urban bridge operation period was carried out based on the analysis theory of the five-element connection number set pair. Based on the establishing a risk evaluation index system of urban bridges in operation period, the G1 method and the entropy weight method were used to calculate the subjective and objective weights, and the combined weighting method of game theory was introduced to determine the comprehensive weight coefficient of the evaluation index, and the risk situation assessment model of urban bridge operation period was constructed based on the five-element connection number. Finally, the feasibility and effectiveness of the model were verified by the operational risk assessment of a bridge in Chongqing. The results show that the associated potential of the urban bridge is in the same potential area, and the bridge is in a low risk state as a whole, and the risk assessment results are consistent with the actual investigation . The evaluation model can effectively analyze the risk status and change trend of urban bridges during the operation period, which can provide beneficial support for the operation risk management and control of urban bridges.