Based on the regional measured temperature, four common probability distribution models were proposed to fit the probability distribution of the daily temperature extremes in different seasons at the bridge location. The fitting of each model was evaluated through 5 performance indexes and the optimal probability distribution model was selected. Based on the optimal probability distribution model, the maximum and minimum temperature values with the return periods of 20 a, 50 a, and 100 a at the bridge location were calculated subsequently. The finite element model of a long-span steel box girder suspension bridge was established using ANSYS. Based on the established model, the effects of temperature variation of different structural components on the bridge's natural frequency and displacement was studied considering the extreme temperature. The influence of restraint systems such as central buckle, vertical supports and expansion joints on the temperature-induced effect of the bridge was further studied. The investigated results show that, except for the first-order symmetrical transverse bending frequency of the stiffening girder, the natural frequencies of the others are negatively correlated with the temperature of the full bridge; When the temperature of the pylons and stiffening girder of the suspension bridge rises or falls by 25℃ respectively, the changes in the natural frequency are all within 5%; When the temperature of the main cable of the suspension bridge is reduced by 12℃, the anti-symmetric vertical vibration frequency of the stiffening girder will increase significantly by about 12%; In addition, the vertical displacement response of the stiffening girder and the vertical and longitudinal displacement response of the bridge tower are linearly related to the temperature variation. And the longitudinal displacement of the stiffening girder is mainly affected by the temperature variation of the stiffening girder. The longitudinal displacement rate of Jianshui side and Yuanyang side are 4.7 mm/℃ and 3.3 mm/℃, respectively; The vertical displacement and rotation angle of the stiffening girder ends are mainly affected by the temperature variation of the main cable; The influence of the vertical support and the longitudinal limit device of the expansion joint on the temperature-induced displacement response of the bridge is negligible, but the central buckle will cause a sudden change in the internal force of the short suspender at the middle of the bridge.