Aims <p>Soil microbial communities in karst wetlands significantly affect soil health and quality, and are critical for maintaining the stability of wetland ecosystems. Further research is needed to determine how karst wetland litter decomposition drives shifts in soil microbial community structure and metabolic function.</p> Methods <p>In this study, high-throughput sequencing technology and the Biolog Ecoplate™ carbon matrix metabolism measurements -were used to assess and analyze the physicochemical characteristics, structural makeup of microbial communities, and carbon source utilization of the dominant vegetation litter and soils in Huanglong karst wetland.</p> Results <p>The results demonstrated that, overall, the soils of the Huanglong Karst Wetland exhibited weak humus properties. Birch leaves with low C/N would exhibit a higher degree of decomposability among the four major vegetative litter, which would encourage the buildup of organic carbon in the surface soil. While total nitrogen and total phosphorus were the most significant environmental factors influencing the spread of the fungal community, litter C/N, soil organic carbon, and soil pH were the primary environmental factors influencing the distribution of the bacterial community.</p> Conclusion <p>Overall, litter decomposition increased soil nutrient levels, and elevated nutrient levels changed patterns of carbon use, causing variations in the metabolic activities of soil microbes under various litter. The study’s findings have significant implications for the involvement of soil microbes in the decomposition of litter and offer scientific references for both the application of wetland conservation strategies and the comprehension of the cycling dynamics of karst wetland ecosystems.</p>