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Thunderstorm gale is one of the main meteorological disasters affecting railway construction and transport safety. As a trunk railway connecting Sichuan Province and Tibet Region, the Sichuan-Tibet railway is known as the “most difficult railway” because of its complex geographical situation and diverse climate characteristics. This paper aims to quantitatively analyze the wind field characteristics in the Sichuan-Tibet region, provide the scientific basis for the construction of the Sichuan-Tibet railway, and the monitoring, reducing, early warning and risk assessment of disasters along the railway. The spatial distribution characteristics and temporal variation of the wind speed in the Sichuan-Tibet region and along Sichuan-Tibet railway stations are analyzed using the NCEP FNL surface wind data from 2000 to 2020, ground meteorological stations’ wind speed data from 2014 to 2020 and extremely wind speed data from 2006 to 2020. The results show that: (1) The wind force in the west of the Sichuan-Tibet region is higher than that in the east, and the wind speeds in the inland of the plateau are higher than those in the southeast edge of the plateau and Sichuan Province. Wind speed is the largest from November to March of the next year on the plateau, with a monthly average wind speed of more than 7 m/s in the northern and southern edges of the plateau. Wind speeds in summer and autumn are the smallest in the plateau. (2) The wind fields of Lhasa Station, Nyingchi Station, Ya’an Station and Chengdu Station along the Sichuan-Tibet railway are selected for analysis. The wind speeds show a decreasing trend from the west of the plateau to the east. (3) During the study period, the mean wind speed and maximum wind speed along the Sichuan-Tibet Railway show an obvious increasing trend from 2018 to 2020, and the number of strong wind days in Lhasa and Nyingchi also increased. Since 2018, the wind speed along the Sichuan-Tibet railway has increased, and the wind risk to the railway was increasing.