Abstract:Investigations were carried out on horizontal and vertical distributions of soil gamasida in Picea and Abies forest,Larix gmelini forest,Alnus hirsuta forest,Betula platyphylla forest and broad-leaved and Pinus koraiensis mixed forest in the Xiaoxing'anling.The results indicate that Gamasellus montanus and Zercon xiaoxinganlingensis are distributed extensively in all habitats,and only in one type of habitat has a huge variety of gamasida species and the more the species exist in the habitat,the more obvious the extensively habitats is.According to Jaccard's similarity index analysis,the soil gamasida communities in Larix gmelini forest are the most similar to those in Alnus hirsuta forest,and the soil gamasida communities in Picea and Abies forest and Alnus hirsuta forest are the least similar to those in Alnus hirsuta forest and Betula platyphylla forest.The vertical distribution of soil gamasida generally shows surface enrichment,but it is different in each habitat.The higher the organic matters and total N in soil,the more the species of soil gamasida and the bigger their populations are.Most of soil gamasida tend to live in slightly acid habitats.