During the service period of bridges, the degradation of bearings and expansion joints’ performance will affect the main girder’s normal expansion and contraction movement. To accurately evaluate the working status of suspension bridge bearings and expansion joints in the short term, taking a kilometer-level suspension bridge as an example, on the premise of studying the seasonal correlation characteristics between girder end displacement-temperature, a short-term status analysis method for key constraint devices based on the correlation characteristics between girder end displacement-temperature was proposed and validated from various aspects such as simplified modeling of girder end constraints, monitoring, and testing of suspension bridges. The analysis shows that: there is a significant linear correlation between the girder end’s displacement and temperature, and the higher the main girder’s temperature, the greater the correlation model’s slope between the two. Influenced by the temperature change, the slope of the correlation model changes by about 40% to 50% within a year. To extract the stable slope of the girder end’s displacement temperature correlation model after normalizing the temperature environment under normal operating conditions of the bridge, it is proposed to use the mathematical relationship between the girder end displacement-temperature correlation model’s slope and temperature to eliminate the influence of temperature changes on the parameters of the girder end displacement-temperature correlation model. The proposed short-term status analysis method was used to analyze and judge the working status of constraint devices on the background bridge, and the judgment results were compared with on-site inspections and maintenance records to confirm the feasibility and rationality of this method. This provides an effective basis for further establishing a key constraint device status warning system.