Soil nematode community composition and diversity in six slope positions (lowland, ecotone, middle windward, top slope, and upper and lower leeward) and at three soil depths (0-20, 20-40 and 40-60 cm) along an active sand dune were studied in the Horqin Sandy Land. The results showed the significant effect of the slope position on soil nematode communities, but no of soil depth. The abundance and diversity of soil nematodes were higher in lowland and low leeward slope than in ecotone and middle windward slope. Significant differences in the abundances of total nematodes, bacterivores, fungivores, plant parasites and omnivores-predators were observed among slope positions. Only the abundance of bacterivores at different soil depths was significantly different. Soil moisture and electronic conductivity were the main factors which affected the spatial distribution pattern of soil nematode communities. The variation in soil microenvironment along an active sand dune could be reflected by the change in distribution pattern of soil nematode communities.