Total genomic DNAs were extracted from soil microorganisms in four soils different in fertilization treatment with the direct extraction method：The four treatments were CK (soil without fertilization)，F1 (low in fertilization level，N∶P₂O₅∶K₂O to 0.1 g kg^-1：0.075 g kg^-1∶0.15 g kg^-1)，F2 (normal in fertilization level，N∶P₂O₅∶K₂O to 0.2 g kg^-1∶0.15 g kg^-1∶0.3 g kg^-1) and F3 (excessive fertilization，N∶P₂O₅∶K₂O to 1.0 g kg^-1∶0.75 g kg^-1∶1.5 g kg^-1) 16S rDNAs of the extracted DNA were amplified using bacterial universal primers and clone libraries set up PCR-RFLP analysis was carried out with restriction endonuclease Rsa I and HhaI，and 146，133，187 and 170 types of restriction endonucleases were obtained from these samples. Statistical analysis of the data using α diversity measurement，which，revealed that the four treatments followed an decreasing order of F2 > F3 > CK > F1 in terms of bacterial diversity and species abundance，indicating that proper fertilization was conducive to bacterial diversity in soil. Variation coefficients of indices of λ，R₂， d_Ma and E between different treatments fell in the range from 12.86 % to118.9 %，especially for Simpson index λ，which was the most sensitive，and varied the sharpest. Results of sequencing and phylogenetic analysis proved clearly that，compared with CK，the fertilization treatments demonstrated obvious changes in distribution of dominant bacteria community.