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Soil enzyme activities play key roles in soil biochemical processes. Enzymes are sensitive to environmental changes. To investigate the effects of vegetation and permafrost on the soil quality in the Qinghai-Tibetan Plateau, this study examined the enzyme activities of invertase, amylase, catalase, polyphenol oxidase, urease, and alkaline phosphatase in the soils under different vegetation and permafrost conditions of the northern fringe of the permafrost regions in the Qinghai-Tibetan Plateau. In addition, 19 soil physio-chemical variables including moisture, bulk density, organic matter, total nitrogen (TN), phosphorus (P), total potassium (TK), and pH, were investigated. The results showed that the environmental variables and enzyme activities varied in the soils from the wet meadow to the meadow where permafrost exists. The soil from the alpine desert showed the lowest enzyme activity and the lowest organic matter content, whereas the soils from the alpine steppe showed some similarities with the meadow and the steppe. meadow. The statistical analyses demonstrated that the soil properties were greatly affected by the vegetation and the permafrost, and the enzyme activities were good indicators of soil quality. There were no obvious differences between the soils from the meadow and the wet meadow, which may indicate that the wet meadow ecosystems in this fringe area are more vulnerable than those of the continuous permafrost regions.