【Abstract】 Soil protozoan is the third largest taxon in soil biota and an important biological regulator for soil organisms and biochemical activities because of its biodiversity predacity and enormous biomass in soil. Different trophic types such as photosynthetic autroph, saprotroph and predacity existed in protozoan. Since predation not only controls the bacteria community but also stimulate nutrient transformation and carbon cycling, the study on protozoan community structure and ecological function is one of the bases for elucidating the soil fertility. The article reviewed the research progresses in protozoan community, trophic types, ecological function and application in soil.更多还原