To study the community composition, vertical structure, diversity and seasonal dynamics of soil fauna in Kmeria septentrionalis forest which is the first-class state protected plant in China,a monthly investigation was conducted between Mar., 2012 and Jan., 2013 in litter layer and soil layers with the depths of 0-5 cm, 5-10 cm,10-15 cm and 15-20 cm. A total of 12 937 of soil fauna individuals, belonging to 6 phyla,11 classes and 30 groups, respectively, were collected in 2 200 soil samples during the study. Two dominant groups,Acarina and Collembola, accounted for 74.69% of the soil fauna individuals. Five common groups, Nematoda, Oligochaet-a opisthopora,Oligochaeta plesiopara, Hymenoptera and Diptera, accounted for 22.26%. The A/C value <1. The vertical distribution of soil fauna groups and individuals in the soil profiles showed an surface accumulation,but no obvious decreasion layer by layer in some months and varied with the change of seasons. The seasonal change pattern of soil fauna group number of Kmeria septentrionalis forest was autumn＞winter＞spring＞summer. The number of soil fauna individual was autumn＞summer＞spring＞winter. The diversity of soil fauna groups was autumn＞spring＞winter＞summer.