Abstract: OBJECTIVE With soils from the field which has been planted no hedyotis diffusa， planted hedyotis diffusa once and planted hedyotis diffusa twice as the objects of study， this paper aims to analyze the effects of hedyotis diffusa continuous copping on the soil nutrient and the number of edaphon.METHODS The number of bacteria， fungi and actinomycetes in soils were assayed with nutrient agar medium， rose Bengal agar medium and Gause's agar medium respectively.RESULTS The planting of Hedyotis diffusa increased the number of edaphon in soil， especially in rhizosphere， and showed rhizosphere effect. However， continuous cropping of Hedyotis diffusa decreased the number of bacteria and actinomycetes in soil， while increased the number of fungi.CONCLUSION Hedyotis diffusa continuous cropping affects the balance of microbial community structure in soil.