Karst desertification control forests are essential for ecosystem multi functionality, but the trade-offs/synergies are unclear for forest ecosystem services. In order to clarify the trade-offs/synergies, this study was conducted on eight forest communities in a karst desertification control area and was based on vegetation surveys and structural and functional monitoring. It analyzes water holding capacity, species diversity, soil conservation, and carbon storage characteristics and their trade-off/synergies. The results indicate the following: (1) TheCladrastis platycarpa+Cotinus coggygriacommunity (H1) had the highest water holding capacity and species diversity with values of 252.21 t·hm−2and 2.56, respectively. Soil conservation was highest in theZanthoxylum bungeanum+Glycine maxcommunity (H6), with an index value of 1.56. Carbon storage was the greatest in theTectona grandiscommunity (H8), at 103.93 t·hm−2. The results of these studies have shown that there are significant differences in different types of forest community ecosystem services. (2) Water holding capacity, species diversity, soil conservation, and carbon storage, all have synergistic relationships, suggesting a trend towards synergistic enhancement between the services. (3) The species diversity of the forest ecosystems was shown to be in a trade-off with carbon storage and soil conservation, which suggests that the services are in competition with each other. To further improve the service capacity of forest ecosystems, the trade-offs between the regulation of forest community structure and function and the improvement of services should be optimized.