The results showed that burning turf could accelerate the decomposition of organic matter, increase the available nutrient contents and raise grass output. But after 3-4 years of burning turf, the contents of available nutrients in the soil decreased obviously and the grass output dropped rapidly, Burning seriously destroyer the soil enzyme so that urease and protease activities could be recovered to 50-80% of the original levels, but alkaline phosphatase, catalase and invertase to only 20-40% of the original levels. Accumulation of organic matter and the activities of soil enzymes tended to be enhaned as time went on. In alpine meadow soil the enzymatic activities were closely related to organic matter content but little related to soil available nutrient content and grass output. So the content of organic matter and the activities of soil enzymes could not be taken as the indexes of soil fertility.