Abstract: Seven low-temperature adapting Bacillus strains growing under 4-10℃ were isolated from plant rhizospher soil in frozen desert of Kunlun Mountain. Identification via biochemistry, BOX-PCR, ERIC-PCR fingerprint, 16S rDNA sequence and gyrB sequence showed that six strains were B. simplex, while the other one was B. malacitensis. Tests on antimicrobial and growth-promoting activities indicated that they presented obvious antagonism against both Sclerotinia sclerotiorum and Xanthomonas oryzae pv. oryzae, two important plant pathogens. Furthermore, strain KLD2 (B. simplex) and KLD5 (B. malacitensis) were demonstrated to be highly capable to increase root length, fibrous root quantity, fresh weight and seed germination of both Arabidopsis thaliana and maize . This study indicated that these low-temperature adapting Bacillus PGPR strains are of high potential for application in agriculture.