Abstract:[Objective] Extracting the metabolites of hydrothermal Bacillus sp. SY27F from deep-sea hydrothermal vents, the antibacterial and antitumor activity of metabolites were assayed.[Methods] The antibacterial activity of the secondary metabolites was determined by the method of paper disk and microbroth dilution method, and the anti-tumor activity of the secondary metabolites was evaluated by CCK-8 method.[Results] The bacteriostatic experiments showed that the metabolites of thermophilic Bacillus sp. SY27F have antibacterial effect on Escherichia coli and Staphylococcus aureus, with MICs of 1.56 mg/mL and 3.13 mg/mL, respectively. Cell cytotoxicity assay showed that the metabolites have the effect of inhibiting cell growth in tumor cells (A549, HepG2, HeLa and MCF-7), with IC50 values of 0.390 mg/mL, 0.451 mg/mL, 0.704 mg/mL and 1.105 mg/mL, respectively. Compared with HepG2, the normal liver cells (L02) showed good biocompatibility.[Conclusion] The metabolites of thermophilic Bacillus sp. SY27F have antibacterial and antitumor activity, and can provide resources for the search of novel compound of antibacterial and antitumor activity.