Desert grassland soil microbial communities are extremely sensitive to precipitation changes. Taking the desert grassland in Yanchi County, Ningxia as the research object, this study simulated five precipitation gradients (decreasing 33% of precipitation, decreasing 66% of precipitation, natural precipitation, increasing 33% of precipitation, and increasing 66% of precipitation) by using the shelter technology to systematically study and research the effects of precipitation changes on the desert grassland soil microbial communities. The results showed that: 1) the short-term precipitation treatments had insignificant effects on plant diversity and richness, significant effects on plant above-ground and below-ground biomass partitioning, and no significant effects on soil carbon, nitrogen, and phosphorus stoichiometry. 2) The effects of precipitation on soil bacterial diversity were smaller than those of fungi, but both bacterial and fungal diversity increased in the reduced-water treatments, bacterial diversity decreased in the water-increased treatments, and fungal diversity increased in the 33% water-increased treatment was the highest, and the lowest in water-increasing 66% from the treatment.3) Precipitation changed the community composition of soil microorganisms, with small differences in bacterial community composition, insignificant differences in fungal community composition at the gate level, and significant changes at the genus level in both water-reducing and water-increasing treatments.4) Differential species were more fungal than bacterial at the genus level, and the difference in species between treatments was more pronounced in the fungal species than that in the bacterial ones.5) Soil carbon, nitrogen, and phosphorus levels was negatively correlated with bacterial diversity and positively correlated with fungal diversity, and plant characteristics were negatively correlated with soil bacterial and fungal diversity as a whole; the effect of environmental factors on fungal diversity was significantly higher than that on bacterial polytrophicity, and the variance of fungal differential species was greater under different precipitation gradients, while that of bacteria was smaller. Fungi were more sensitive than bacteria in responding to short-term treatments of precipitation changes in desert grasslands.