The freeze-thaw cycle of near-surface soil in the perennial permafrost region of the Qinghai-Xizang （Tibetan）Plateau plays a crucial role in regulating water and energy exchange between the soil and the atmosphere. Investigating its spatiotemporal characteristics and response to climate change is essential for understanding the mechanisms driving climate change on the plateau. In this study，we calculated near-surface freeze-thaw parameters-including the start and end times of soil freezing，thawing duration，and freezing duration-across the perennial permafrost region of the plateau from 1980 to 2017 using the Common Land Model 5. 0（CLM5. 0）. We further analyzed their spatiotemporal variations and correlations with temperature，precipitation，snow depth，and vegetation index. The results show that：（1）The onset of near-surface soil freezing in the plateau’s permafrost region occurs between September and mid-to-late October，while the thawing period ends between February and May. Semi-humid regions have the longest thawing duration，whereas semi-arid regions have the shortest，with an average difference of 15 days. The freeze-thaw status of permafrost soil on the plateau exhibits significant changes. Except for areas near the Karakoram Mountains，most permafrost regions show a decreasing trend in freezing duration and an increasing trend in thawing duration. The average growth rate of soil thawing duration across the plateau is 2 d·（10a）⁻¹，with the most significant increase observed in semi-humid regions， reaching 4 d·（10a）⁻¹.（2）The freeze-thaw parameters of the plateau's permafrost are associated with geographical factors. In the latitude range of 29°N-36°N and longitude range of 82. 5°E-103°E，the thawing duration shows an increasing trend；however，the rate of change decreases in some areas while increasing in others. Additionally，as elevation increases，the growth rate of thawing duration declines.（3）The duration of permafrost thawing is significantly correlated with snow depth，near-surface temperature，precipitation，and vegetation index，though these relationships vary across different climatic regions. Near-surface temperature exhibits a strong positive correlation across all regions，making it the primary driver of freeze-thaw changes. Precipitation and snow depth show positive and negative correlations，respectively，with particularly strong correlations in semihumid areas. The vegetation index is positively correlated with thaw duration in all regions，with the strongest correlation observed in semi-arid areas.（4）The relationship between thawing duration and seasonal climatic fac‐ tors varies. Near-surface air temperature exerts a significant influence on the freeze-thaw process at seasonal scales，with the most pronounced impact occurring in spring. Precipitation is positively correlated in summer but negatively correlated in winter. Both snow depth and vegetation index are significantly correlated with thawing duration in semi-arid and semi-humid regions during spring，exhibiting negative and positive correlations，respectively.（5）Near-surface temperature influences the freeze-thaw cycle in the plateau’s perennial permafrost region during both dry and wet seasons. However，the effects of snow depth，precipitation，and vegetation index are more pronounced during the wet season.