An alkaliphilic and slightly halophilic Gram-positive rod, designated strain F10, was isolated from Haoji soda lake in Inner Mongolia Autonomous Region, China. Strain F10 grew optimally in the presence of 3% (W/V) NaCl, pH 9.5 and 37 degrees C. It was facultatively anaerobic, motile with peritrichous flagella, sporulating, catalase- negative. The (G + C) content of the DNA was 40 mol%. The cell wall contained meso-DAP. Phylogenetic analyses based on 16S rDNA sequences comparisons indicate that strain F10 was a member of the genus Amphibacillus. DNA-DNA similarity of less than 30% with the described species of Amphibacillus supported the view that this organism represented a new species of the genus Amphibacillus. The name Amphibacillus haojiensis sp. nov. is proposed.