Plant functional groups enable us to understand the ecological adaptation strategies of plants to changes in the external environment and resources at a higher scale. The variations of plant functional traits are the keys to analyzing the response mechanisms of plants to environmental changes. Here, based on the extensive plant surveys and sampling, the plant functional groups and functional traits in the KRD (karst rocky desertification) ecosystem in southern China were studied. The following results and conclusions were obtained: The 53 dominant plant samples can be clustered into four functional groups based on their functional trait matrix: PFG1 (high-storage and stress-tolerant arbors), PFG2 (resource-conserving shrubs), PFG3 (fast-growing resourceutilizing herbs), and PFG4 (drought-tolerant conservative herbs). The relative abundances of different functional groups at different KRD degrees are obviously different. Different functional groups have significantly different survival strategies in the KRD environments. Functional traits play an important role in plants' adaptation to the KRD environment. PFG1 and PFG2 show a conservative resource-preservation strategy, optimizing survival through vertical growth and water retention. PFG3 shows a resource-utilization strategy, and PFG4 shows a conservative resource-utilization strategy. The present results reveal the ecological adaptation strategies of KRD plant functional groups to the environments and are of great significance for the scientific KRD vegetation restorations.