Abstract: The wind field in mountainous gorge is significantly affected by terrain, and its characteristics are quite complex, which has a significant impact on the wind-induced vibration response of the suspension-braced transmission structure crossing mountainous gorge. In order to obtain the wind field characteristics of mountain gorge and analyze their impact on the wind-induced vibration response of the suspension-braced transmission structure, the gorge wind field where a suspension-braced transmission structure is located was investigated via a field measurement at first. Based on measured data, the mean and fluctuating wind characteristics of the wind field were analyzed, and the measured power spectrum was fitted. A nonlinear finite element analysis model for wind-induced vibration of the suspension-braced transmission structure considering the effect of gorge wind field was developed based on the characteristics of the gorge wind field. The impact of the gorge wind field on the wind-induced vibration response of the suspension-braced transmission structure was investigated through the proposed model. The results show that: The distribution of wind direction samples with lower mean wind speed is more discrete, while for samples with mean wind speed of no less than 8 m/s (i.e., strong wind samples), the wind direction is more concentrated. The correlation between wind attack angle and wind direction angle of strong wind samples is significant. The mean values of the turbulence intensities of longitudinal, lateral and vertical are 0.25, 0.20 and 0.15, respectively. The measured power spectrum has higher spectral values than the theoretical spectrum, and it appears to be higher in the high-frequency range. Compared with the wind field simulated by the theoretical spectrum, the mean and mean square deviation of midpoint lateral displacement of the conductor in the gorge wind field increase by 3.16% and 3.26%, respectively, while the mean and mean square deviation of vertical displacement increase by 7.85% and 6.62%. The mean and mean square deviation of midpoint lateral displacement of the supporting-conductor suspension cable considering the effect of gorge wind field are close to those of the wind field simulated by the theoretical spectrum, while the mean and mean square deviation of vertical displacement increase by 62.14% and 15.28%, respectively.