Changes in precipitation patterns caused by global warming is a common phenomenon, which affects soil carbon respiration and soil environmental characteristics. Soil microbial community structure is an effective indicator to reflect this change. In this paper, we take the soil of the south subtropical monsoon evergreen broad-leaved forest in Dinghu mountain as research object. Our object explores the influence of precipitation changes on soil microbial communities in different soil layers. Three experimental treatments are included: The precipitation is constant but the times of precipitation increases, reduce the amount of precipitation by 50%, normal precipitation (control group). Soil microbial biomass was measured by the method of phospholipid fatty acid (PLFA). The experiment results show that: (1) The three precipitant treatments did not significantly affected the amounts of soil microbial total PLFAs, bacteria PLFAs, fungi PLFAs, actinomycetes PLFAs and arbuscular mycorrhizal fungi PLFAs of the same layer in the rainy premonsoon season. (2) In the layer 0~10 cm, the relative abundance of bacterial, gram-positive bacteria, gram-negative bacteria, fungi, actinomycetes, arbuscular mycorrhizal had not significant difference, which indicated the soil microbial community structures were similar under different treatment conditions. (3) In the layer 10~20 cm, the relative abundance of bacterial show obvious difference (P<0.05) in the soil microbial community structure. (4) There was the negative correlation between the soil pH value and the total PLFAs of soil microbial biomass (P<0.01) under different experimental treatment.