Soil greenhouse gas (GHG) emissions play an important role in regional climate feedback on the Qinghai-Tibetan Plateau (QTP). Previous studies have focused on soil GHGs based on observations within a limited space on the QTP, however, the regional GHG emissions remain unclear. Analyzing soil samples from 25 sites along a 2,700 km transect across QTP, we showed significantly higher soil CO₂ and N₂O emission rates in alpine meadows than other upland grassland types, but similar soil CH₄ uptake rates across all grassland types. The spatial variations of total soil GHG balance were dominated by CO₂ emission. We found that CO₂ emission was primarily constrained by high soil pH, low soil moisture and nutrient availability, and fungal abundance, N₂O emission was inhibited by high soil pH, while CH₄ uptake was dominated by methanotrophic abundance. Furthermore, we estimated a current regional total soil GHG balance of 144.4 Tg CO₂-eq yr⁻¹ for surface soil across Tibetan alpine grasslands, which increased by 17.6%, 24.8%, and 38.9% under warming scenarios of 1.5℃, 2℃ and 3℃, respectively. Our results provide a baseline for regional soil GHG emissions responding to climate warming on the QTP.