Abstract: In order to approach the biological indicators of soil health,the activity of soil enzymes and its relations with the soil fertility in 0—5 cm horizon under different vegetation types were studied.Results showed that the activity of soil enzymes was obviously different.Among the different vegetation types,the activity of soil enzymes under Tilia mandshurica forests was the highest except peroxidase,whereas that under shrub-grass was the lowest.The activity of soil urease and alkaline phosphate under shrub was higher than that under the mixed forests.Activity of soil catalase and phosphate under Larix principis-rupprechtii forests was higher than that under Pinus tabulaeformis. The relations between enzyme activity and soil fertility showed that urease,acid phosphate,alkaline phosphate and catalase were all had good correlations with soil fertility.Secondly,the correlation coefficient of the total phosphate was higher than the individual.Polyphenol oxidase and peroxidase were not related to soil fertility.