In this study, the mixed environmental genomic DNA was isolated directly from the mud volcano soil in Usu county of Xinjiang. The 16S rRNA genes were amplified with bacterial universal primers and cloned into the pGEM-T Easy Vector to construct a16S rRNA clone library．The total 150 clones were selected by amplified rDNA restriction analysis（ARDRA） using restriction enzymes Hae Ⅲ. Of these, 16 restriction fragment length polymorphism（RFLP）types were used for sequencing. A part of these sequences were closely related to the phylum: Proteobacteria，Firmicutes，Fusobacteria and Actinobacteria (>97% sequence similarity), while another portion showed less affiliation with known taxa (<97% sequence similarity) and might represent novel taxa. The results indicated that the mud volcano in Usu county of Xinjiang is rich in microbial species，which is worth further studying.