Abstract: In this study, the effects of different levels of nitrogen and silicon fertilizers on microbial community structure of rhizosphere soil of rice were investigated to provide reference for rational application of silicon and nitrogen fertilizers in rice. The silicon source of silicon fertilizer selected Na₂SiO₃, and six treatment groups of silicon and nitrogen fertilizers were set up. Denaturing gradient gel electrophoresis (PCR-DGGE) was used to explore the effects of silicon application at different nitrogen levels on the community structure of bacteria, fungi and archaea in the rhizosphere soil of rice. The results showed that there was no significant change in the bacterial community diversity of rhizosphere soil of rice in the low and medium nitrogen treatment groups, while it was shown an increasing trend in the high nitrogen treatment group. However, the effects of silicon treatments were neither obvious on the bacterial community structure at different nitrogen levels, nor on the fungal community structure at the low and medium nitrogen levels. Compared with the low nitrogen level, the fungal diversity with high nitrogen level in the rhizosphere soil of rice was decreased significantly. But it was increased by silicon addition, promoting the fungal taxa growth of Coniochaeta prunicola, Paecilomyces farinosus, Ascomycota sp. and Thermothelomyces hinnuleus, inhibiting the growth of Fusarium equiseti. With the increase of nitrogen level, the diversity of archaea community was increased, but there was no significant effect after silicon addition. These results indicated that bacteria, under different nitrogen levels, the application of silicon fertilizer with Na₂SiO₃ as silicon source had no significant effect on the community structure of bacteria and archaea in the rhizosphere soil of rice. However, at high nitrogen level, adding silicon fertilizer could significantly increase the diversity of soil fungal community.