Bacterial diversity associated with Baer Soda Lake in Inner Mongolia of China was investigated using a culture-independent method. Bacterial 16S rRNA gene libraries were generated using bacterial oligonucleotide primers, and 16S rRNA gene sequences of 58 clones were analyzed phylogenetically. The library was dominated by 16S rDNAs of Gram-negative bacteria (24% alpha-Proteobacteria, 31% beta-Proteobacteria, 33% gamma-Proteobacteria, and 2% delta-Proteobacteria), with a lower percentage of clones corresponding to Gram-positive bacteria. Forty cloned sequences were similar to that of known bacterial isolates (> 97% sequence similarity), represented by the species of the genera Brevundimonas, Comamonas, Alcaligenes, Stenotrophomonas, and Klebsiella. Eighteen cloned sequences showed less affiliation with known taxa (< 97% sequence similarity) and may represent novel taxa.