The purpose of this study was to investigate the effects of different types of straw returning on the microbial community structure in a dryland red soil. The field experiment was conducted with different types of straw returning in corn mono-cropping system at the National Agro-Ecosystem Observation and Research Station in Yingtan. The sequencing of 16S rRNA gene was used to investigate the effects of different types of straw returning on the diversity and structure of soil bacteria community. The results showed that:1) the straw returning treatments (NPKS, NPKSM and NPKB) significantly promoted soil fertility, with the highest effects under the NPKSM treatment (straw plus pig manure); 2) the straw returning treatments significantly increased the bacterial diversity compared to the chemical fertilization treatment; and 3) soil available phosphorus and organic carbon were the two most important predictors of the bacterial diversity, while available potassium, pH, total phosphorus and total nitrogen were the significant predictors of the bacterial community structure. The results provide the scientific basis for the synergistic improvement of biological functions and soil health in agricultural ecosystem from the perspective of promoting soil fertility and microbial diversity.