Abstract: A strain of silicate bacteria, B925, isolated from the rhizosphere soil of tobacco plants in Fujian Province, it showed inhibition on Phytophthora parasitica var. nicotianae and other plant pathogens, and inhibited the former effectively either in the form of fermentation liquid or the aseptic filtrate of the liquid.The fermentation liquid at a dilution of 10 promoted the germination of tobacco seeds.The results in vitro inoculated test showed that the fermentation liquid of B925 prevented the spread of tobacco black shank disease, and the indoor pot experiment indicated the control effect was 58.3%.By 16S rDNA sequence analysis, strain B925 was identified as Bacillus mucilaginosus.