In 18 years old,22 years old and 38 years old Larix-principis-rupprechtii plantations in Saihanba Forestry Station of Hebei Province,soil quality indicators such as physicochemical properties,enzymatic activities and microbe quantity were researched comprehensively.The key indexes and varying patterns of soil quality were understood by data analyzing.Soil indicators have significant differences in even-aged stands.With the increasing of soil depth,the soil bulk density and pH values magnify correspondingly,while the values of the other 12 indicators(including soil water content,capillary water holding capacity,capillary porosity and so on) have an adverse trend.The same indicator among uneven aged stands also has significant difference.The optimal indicators in 18 years old stands are the catalase activity and bacteria quantity,while SWC,capillary water holding capacity,capillary porosity,organic matter(OM),urease activity and fungi in 22 years old stands,and soil bulk density,total K,rapidly-available phosphorus,total nitrogen and actino-mycetes in 38 years old.The results of principal components analysis(PCA) showed that the soil bulk density,capillary water holding capacity,capillary porosity,quantities of OM,actinomycetes and fungi are optimal indicators of soil quality.The comprehensive score of Larix-principis-rupprechtii soils in 18,22 and 38 years old plantations are 0.122,0.253 and.375,respectively.The highest score of soil quality in 22 years old stands suggests that the soil is the best.