【Objective】Grasslands, as one of the most extensive ecosystems, play an important role in regulating the global carbon cycle through the decomposition of soil organic carbon (SOC) pools. However, the effects of global warming on SOC decomposition dynamics, and the underlying microbial and enzymatic regulatory mechanisms remain unclear. Here, we investigated how warming alters the decomposition dynamics of active, slow, and passive SOC pools, with a focus on microbial community composition and extracellular enzyme stoichiometry. 【Method】This study was conducted using surface soil collected from semi-arid grasslands on the Loess Plateau in a long-term incubation experiment. Soil samples were incubated at two controlled temperatures (15 °C and 25 °C) under constant temperature and humidity for 553 days (~1.5 year). During the incubation, soil respiration rates, microbial biomass carbon (MBC), extracellular enzyme activities, and microbial community compositions were systematically monitored. 【Result】The results showed that incubation at 25 °C significantly increased soil respiration rates, cumulative carbon emissions, and the decomposition rates of the three SOC pools (active, slow, and passive) compared to 15 °C. However, the magnitude of this enhancement diminished over time. Among the SOC pools, the active pool exhibited the most rapid decline in respiration rate, followed by the slow pool, with the passive pool showing the slowest decline. Additionally, microbial biomass carbon and bacterial diversity decreased more rapidly at 25 °C, accompanied by significant shifts in microbial community composition. The relative abundance of copiotrophic microorganisms, such as Proteobacteria and Ascomycota, decreased during the incubation, whereas oligotrophic microorganisms, including Actinobacteria and Ascomycota, increased. Notably, copiotrophic microorganisms were more dominant at 15 °C, while oligotrophic microorganisms were more prevalent at 25 °C. Microbial oxidative metabolism, nitrogen demand, and phosphorus demand increased progressively throughout the incubation, with overall higher levels observed at 25 °C compared to 15 °C. Furthermore, the response of the three carbon pool decompositions to temperature increase was regulated by extracellular enzymes and microbial community composition. Stepwise linear regression showed that under 15 °C incubation, MBC and oxidases were positive regulatory factors for the decomposition of the active and slow carbon pools, respectively. Under 25 °C incubation, NAG (β-1,4-N-acetylglucosaminidase), and AKP (alkaline phosphatase) were positive regulatory factors for the decomposition of the passive carbon pool. The partial least squares path model analysis indicated that incubation temperature and time significantly regulated microbial community composition. The microbial community composition positively regulated extracellular enzyme activity and exerted negative and positive regulation on the decomposition of the slow and passive carbon pools, respectively. Also, extracellular enzymes, as key regulatory factors for the decomposition of the active and passive carbon pools, exerted negative and positive regulation on the decomposition of these pools, respectively.【Conclusion】This study reveals that shifts in microbial community composition, particularly the shift in species with different ecological strategies, play a key role in regulating extracellular enzyme activities and stoichiometry, thereby mediating temperature-induced changes in SOC decomposition dynamics. These findings provide critical insights into the microbial and enzymatic mechanisms that drive SOC turnover under warming conditions, offering valuable evidence to enhance our understanding of global carbon cycling and its feedback to climate change.